Granted (shares) Units granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Short-term foreign bank loans against the lines of credit Line of Credit, Current Acquired intangibles Deferred Tax Liabilities, Intangible Assets Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Aggregate intrinsic value of options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Change in benefit obligation Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Performance assumption change (shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Assumption Change The change in the number of shares under a share-based award plan other than a stock option plan due to a change in the performance assumptions. Change in plan assets Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Non-current deferred income taxes Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities 2025 Lessee Operating and Financing Lease, Liability, to be Paid, Year Five Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Noncontrolling Interest [Table] Noncontrolling Interest [Table] LIFO inventory amount LIFO Inventory Amount Goodwill, Purchase Accounting Adjustments Goodwill, Purchase Accounting Adjustments Actuarial net (loss) gain Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax Licensing Agreements Licensing Agreements [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Amortization of ROU assets, Finance lease cost Finance Lease, Right-of-Use Asset, Amortization Preferred Stock Preferred Stock [Member] Security Exchange Name Security Exchange Name Fair value of plan assets at beginning of year Fair value of plan assets at end of year Defined Benefit Plan, Plan Assets, Amount Defined Benefit Plan, Plan Assets, Amount Long-term borrowings, net of debt issuance costs Proceeds from Issuance of Long-term Debt Retirement of treasury common stock Treasury Stock, Retired, Cost Method, Amount Total current liabilities Liabilities, Current Accounts Receivable - Trade Accounts Receivable [Policy Text Block] Other comprehensive income - foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Noncontrolling Interest Settlement Defined Benefit Plan, Plan Assets, Payment for Settlement Performance stock units Performance Shares [Member] Prepaid expenses and other Prepaid Expense and Other Assets, Current Outstanding at beginning of year (USD per share) Outstanding at end of year (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value 2025 Defined Benefit Plan, Expected Future Benefit Payment, Year Five 2.900% Notes (1) Notes 2.90% Due 2020 [Domain] Notes 2.90% Due 2020 Valuation allowance release Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Total lease payments Finance Lease, Liability, Payment, Due ASSETS Assets [Abstract] Investment, Name [Axis] Investment, Name [Axis] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Accounting Policies [Abstract] Accounting Policies [Abstract] Revenue, Major Customer [Line Items] Revenue, Major Customer [Line Items] Operating cash flows from operating leases Operating Lease, Payments 2023 Long-Term Debt, Maturity, Year Three Total lease liabilities Operating & Finance, Lease Liability Present value of lessee's discounted obligation for lease payments from operating and finance leases. Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Purchase Obligations Covered by Purchase Agreements with Various Suppliers Future Maturity Schedule Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] (Losses) gains on cash flow hedging derivatives, after tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Reallocation of undistributed earnings Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired 2021 Lessee, Operating Lease, Liability, to be Paid, Year One Class B common stock Common Class B [Member] Outstanding shares at beginning of year (shares) Outstanding as of December 31, 2020 (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 2024 Lessee, Operating Lease, Liability, to be Paid, Year Four Employee service share-based compensation, nonvested awards, compensation cost not yet recognized Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Allocation of undistributed earnings Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Long-term debt Long-term Debt and Lease Obligation Diversified credit Diversified credit [Member] Diversified credit [Member] State Current State and Local Tax Expense (Benefit) Preferred stock, shares issued: none in 2020 and 2019 Preferred Stock, Value, Issued Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Common stock, par (USD per share) Common Stock, Par or Stated Value Per Share 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Other long-term liabilities Total other long-term liabilities Other Liabilities, Noncurrent Deferred income taxes Non-current deferred tax assets, net Deferred Income Tax Assets, Net Financing cash flows from finance leases Finance Lease, Principal Payments 3.100% Notes Notes 3.10% Due 2021 [Domain] Notes 3.10% Due 2021 Goods in process Inventory, Work in Process, Net of Reserves Valuation Allowance of Net Deferred Taxes SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member] Segment Reconciling Items Segment Reconciling Items [Member] Inventories Total inventories Inventory, Net Measurement Frequency [Domain] Measurement Frequency [Domain] Schedule of Unallocated Mark-to-Market Losses (Gains) on Commodity Derivatives Allocation Of Net Derivative Gains Losses From Economic Hedges To Operating Results Of Reporting Segments Table [Table Text Block] Allocation Of Net Derivative Gains Losses From Economic Hedges To Operating Results Of Reporting Segments Table [Table Text Block] Concentration Risk, Percentage Percentage of employees Concentration Risk, Percentage Share-based compensation arrangement by share-based payment award, expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Number of countries in which products are marketed, sold and distributed (country) Number Of Countries Where Brands Are Martketed, Sold, And Distributed Number Of Countries Where Brands Are Marketed, Sold, And Distributed Fair value of plan assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] Statement [Line Items] Statement [Line Items] Other long-lived assets, not held for sale Other Long-Lived Assets, Not Held For Sale [Member] Other Long-Lived Assets, Not Held For Sale [Member] Class of Stock [Domain] Class of Stock [Domain] Inventories at FIFO FIFO Inventory Amount Performance stock units and restricted stock units Performance Stock Units and Restricted Stock Units [Member] Performance Stock Units and Restricted Stock Units [Member] Statement [Table] Statement [Table] Interest cost Defined Benefit Plan, Interest Cost Type of Restructuring [Domain] Type of Restructuring [Domain] Statistical Measurement [Axis] Statistical Measurement [Axis] Deferred income taxes Deferred Income Taxes and Tax Credits Other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Reclassification to earnings, pre-tax amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] Entity Small Business Entity Small Business Debt instrument, covenant, pre-tax income from operations to consolidated interest expense, minimum Debt Instrument, Covenant, Pre-tax Income From Operations To Consolidated Interest Expense, Minimum Debt Instrument, Covenant, Pre-tax Income From Operations To Consolidated Interest Expense, Minimum Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Short and Long-Term Debt Debt Disclosure [Text Block] Defined Benefit Plan, Plan Assets Measured at Net Asset Value Defined Benefit Plan, Plan Assets Measured at Net Asset Value Defined Benefit Plan, Plan Assets Measured at Net Asset Value Stock compensation Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Percent Actuarial net (gain) loss Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax Amendment Flag Amendment Flag Schedule of Activity Relating to Grants of PSUs and RSUs Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Accrued net interest and penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Share-based compensation arrangement by share-based payment award, number of shares authorized (shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Corporate, Non-Segment Corporate, Non-Segment [Member] Other Other Accrued Liabilities, Current Reclassification to earnings, after-tax amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax Measurement Frequency [Axis] Measurement Frequency [Axis] Accrued Liabilities, Current [Abstract] Accrued Liabilities, Current [Abstract] Schedule of Fair Values and Carrying Values of Long-Term Debt Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Unallocated mark-to-market losses (gains) on commodity derivatives Net gains on mark-to-market valuation of commodity derivative positions recognized in income Derivative, Gain (Loss) on Derivative, Net Proceeds from Issuance of Other Long-term Debt Proceeds from Issuance of Other Long-term Debt Derivative Instruments Derivatives, Policy [Policy Text Block] Employee service share-based compensation, nonvested awards, compensation not yet recognized, stock options Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Deferred tax assets: Deferred Tax Assets, Net of Valuation Allowance [Abstract] Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Balance at Beginning of Period Balance at End of Period SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Schedule of Revenue from External Customers by Products and Services Revenue from External Customers by Products and Services [Table Text Block] Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Income Statement Location [Domain] Income Statement Location [Domain] 2022 Lessee, Operating Lease, Liability, to be Paid, Year Two Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Selling, marketing and administrative expense Selling, General and Administrative Expense Foreign exchange contracts Foreign Exchange Contract [Member] Schedule of Components of Lease Expense Lease, Cost [Table Text Block] 2023 Lessee, Operating Lease, Liability, to be Paid, Year Three Customer-related Customer-Related Intangible Assets [Member] Other non-current assets Total other non-current assets Other Assets, Noncurrent Pirate Brands Pirate Brands [Member] Pirate Brands [Member] Concentration Risk [Table] Concentration Risk [Table] Total assets Assets Schedule of Supplemental Balance Sheet Information Schedule of Supplemental Balance Sheet Information [Table Text Block] Schedule of Supplemental Balance Sheet Information [Table Text Block] 3.200% Notes Notes 3.20% Due 2025 [Member] Notes 3.20% Due 2025 [Member] Exercise Price Range [Domain] Exercise Price Range [Domain] International government/corporate bonds Debt Security, Government, Non-US [Member] Interest expense Interest Expense, Debt Net gains (losses) on commodity derivative positions reclassified from unallocated to segment income Net Gain Loss On Commodity Derivative Positions Reclassified From Unallocated Derivative Gains Losses To Segment Income The amount of gain (loss) from commodity derivative positions reclassified from unallocated derivative (gains) losses to segment income. Corporate (1) Corporate Segment [Member] Outstanding at beginning of year (shares) Outstanding at end of year (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Amortization of prior service (credit) cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Finance leases Finance Lease, Liability, Payment, Due [Abstract] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Cost of Sales Cost of Sales [Member] Schedule of the Changes in the Outstanding Shares of Common Stock Schedule of Common Stock Outstanding Roll Forward [Table Text Block] Common stock, voting rights (vote) Common Stock, Number of Votes Common Stock, Number of Votes 2020 business realignment charges Restructuring Charges, Business Realignment Reserve Restructuring Charges, Business Realignment Reserve Business Acquisitions and Divestitures Mergers, Acquisitions and Dispositions Disclosures [Text Block] Dividends, common stock, cash, additional percentage over Class B common stock dividends Dividends, Common Stock, Cash, Additional Percentage Over Class B Common Stock Dividends Dividends, Common Stock, Cash, Additional Percentage Over Class B Common Stock Dividends Weighted- Average Exercise Price (USD per share) Share-based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price Cash Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents 0.900% Notes (2) Notes 0.900% Notes Due 2025 [Member] Notes 0.900% Notes Due 2025 Total liabilities Liabilities Interest crediting rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Weighted-Average Interest Crediting Rate Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Minimum length of time, hedged in cash flow hedge Minimum Length of Time Hedged in Cash Flow Hedge Minimum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Retirement Plan Type [Axis] Retirement Plan Type [Axis] Defined Benefit Plan, Accumulated Benefit Obligation Defined Benefit Plan, Accumulated Benefit Obligation Less: Imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Net tax expense (benefit) for interest and penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Quoted prices in active markets of identical assets (Level 1) Fair Value, Inputs, Level 1 [Member] Inventories Increase (Decrease) in Inventories 2022 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Two Maximum length of time, hedged in cash flow hedge Maximum Length of Time Hedged in Cash Flow Hedge Other assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Stock repurchases: Share Repurchase Program [Abstract] Share Repurchase Program [Abstract] Net impact of interest rate swaps, debt issuance costs and unamortized debt discounts Debt Instrument, Impact of Derivatives, Unamortized Discount (Premium), and Debt Issuance Costs, Net Debt Instrument, Impact of Derivatives, Unamortized Discount (Premium), and Debt Issuance Costs, Net Additional Paid-in Capital Additional Paid-in Capital [Member] Other (Income) Expense, Net Schedule of Other Nonoperating Income (Expense) [Table Text Block] Other Other Operating Activities, Cash Flow Statement Interest on lease liabilities, Finance lease cost Finance Lease, Interest Expense Accrued expenses and other reserves Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Machinery and Equipment Machinery and Equipment [Member] Common stock, shares, outstanding (shares) Common Stock, Shares, Outstanding Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Capital loss carryforwards Deferred Tax Assets, Capital Loss Carryforwards Revolving Credit Facility Revolving Credit Facility [Member] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Income before income taxes Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Derivative, term of contract Derivative, Term of Contract Property, plant and equipment, net Property, Plant and Equipment [Member] Outstanding (USD per share) Outstanding (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Common stock, shares authorized (shares) Common Stock, Shares Authorized Business acquisitions, net of cash and cash equivalents acquired Payments to Acquire Businesses, Net of Cash Acquired Property, plant and equipment, gross Property, Plant and Equipment, Gross Incremental common shares attributable to dilutive effect of share-based payment arrangements Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Exercise of stock options Proceeds from Stock Options Exercised Federal Deferred Federal Income Tax Expense (Benefit) Performance assumption change Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Assumption Change Weighted Average Grant Date Fair Value The weighted average fair value as of the grant date pertaining to a share-based award plan other than a stock option plan due to a change in the performance assumptions. 3.375% Notes Notes 3.375% Due 2023 [Domain] Notes 3.375% Due 2023 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Schedule of Net Sales and Earnings by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Funded status at end of year Defined Benefit Plan, Funded (Unfunded) Status of Plan Pension and post-retirement benefit plans: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] Income Statement [Abstract] Income Statement [Abstract] 2025 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Five Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Promotional Costs, Estimate Deviation, Percentage (Less Than) Promotional Costs, Estimate Deviation, Percentage Promotional Costs, Estimate Deviation, Percentage Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Other (income) expense, net Other Nonoperating, Gain (Loss) Other Nonoperating, Gain (Loss) Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Basic earnings per share: Earnings Per Share, Basic, Two Class Method [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Interest paid Interest Paid, Including Capitalized Interest, Operating and Investing Activities Use of Estimates Use of Estimates, Policy [Policy Text Block] Expected reduction in the liability for unrecognized tax benefits within the next 12 months Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Allocation of distributed earnings (cash dividends paid) Dividends Schedule of Weighted-Average Assumptions Used in Computing the Benefit Obligation Defined Benefit Plan, Assumptions [Table Text Block] Computer Software Software and Software Development Costs [Member] Investment tax credits and related tax depreciation benefits Income Tax Credits and Adjustments Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Scenario [Domain] Scenario [Domain] Counterparty Name [Domain] Counterparty Name [Domain] Capital additions (including software) Payments to Acquire Property, Plant, and Equipment Consolidation Items [Domain] Consolidation Items [Domain] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Reclassification to earnings due to sale of businesses, pre-tax amount, tax (expense) benefit Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, Tax Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Prior service cost (credit) Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Reclassification Adjustment, before Tax Hedging Designation [Axis] Hedging Designation [Axis] Accumulated impairment loss Goodwill, Impaired, Accumulated Impairment Loss Common Stock Voting Rights, Board Election Percentage Common Stock Voting Rights, Board Election Percentage Common Stock Voting Rights, Board Election Percentage 2026-2030 Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Treasury Stock, Shares [Roll Forward] Treasury Stock, Shares [Roll Forward] Treasury Stock, Shares [Roll Forward] Designated as Hedging Instrument Designated as Hedging Instrument [Member] $34.89 - $96.65 Exercise Price Range One [Member] Exercise Price Range One [Member] Defined Benefit Plans, Minimum Future Employer Contributions in Next Fiscal Year Defined Benefit Plans, Minimum Future Employer Contributions in Next Fiscal Year Defined Benefit Plans, Minimum Future Employer Contributions in Next Fiscal Year Schedule of Business Realignment Activity Restructuring and Related Costs [Table Text Block] Acquired during the period Goodwill, Acquired During Period Quarterly Data (Unaudited) Quarterly Financial Information [Text Block] Common and preferred shares authorized (shares) Common and Preferred Stock, Shares Authorized Common and Preferred Stock, Shares Authorized Property, plant and equipment, useful life Property, Plant and Equipment, Useful Life Inventories Inventories [Member] Goodwill [Line Items] Goodwill [Line Items] Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Amplify Snack Brands, Inc. Amplify Snack Brands, Inc. [Member] Amplify Snack Brands, Inc. [Member] Share-based Payment Arrangement, Option, Exercise Price Range [Table] Share-based Payment Arrangement, Option, Exercise Price Range [Table] Inventory Obsolescence Reserve SEC Schedule, 12-09, Reserve, Inventory [Member] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Finished goods Inventory, Finished Goods, Net of Reserves Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Operating lease liabilities, current Operating Lease, Liability, Current Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Short-term debt, weighted average interest rate Short-term Debt, Weighted Average Interest Rate, at Point in Time Finance leases Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Schedule of the Effect of Derivative Instruments on the Consolidated Statements of Income Derivative Instruments, Gain (Loss) [Table Text Block] Forfeited (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Schedule of Fair Value Estimated on the Grant Date and the Weighted Average Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Gross derivative assets, included within derivative liabilities Derivative Asset, Cash Transfers Receivable (Payable), Change In Quoted Market Prices On The Last Day Of Trading Derivative Asset, Cash Transfers Receivable (Payable), Change In Quoted Market Prices On The Last Day Of Trading Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Corporate bonds Corporate Bond Securities [Member] Schedule of the Classification of Derivative Assets and Liabilities within the Consolidated Balance Sheets Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Accounts Receivable Accounts Receivable [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Interest rate swap Interest Rate Swap [Member] Customer [Domain] Customer [Domain] Cumulative effect of new accounting principle in period of adoption Cumulative Effect, Period of Adoption, Adjustment [Member] Accrued trade promotion reserves Deferred Tax Asset Tax Deferred Expense Accrued Trade Promotion Reserves This element reflects the tax effect as of the balance sheet date of the amount of the estimated future tax effects arising from all other reserves, which can only be deducted for tax purposes when losses pertaining to such reserves are actually incurred. Maximum amount of short term borrowing outstanding Line of Credit Facility, Maximum Amount Outstanding During Period Entity Registrant Name Entity Registrant Name Foreign currency translation adjustments Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Business Acquisition and Divestitures [Line Items] Business Acquisition [Line Items] Business Acquisition [Line Items] Concentration Risk [Line Items] Concentration Risk [Line Items] Operating leases, Weighted-average remaining discount rate Operating Lease, Weighted Average Discount Rate, Percent Global real estate investment trusts Global real estate investment trusts [Member] Global real estate investment trusts [Member] Long-lived and intangible asset impairment charges Long-lived asset and intangible asset impairment charges Asset Impairment Charges Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Less: Imputed interest Finance Lease, Liability, Undiscounted Excess Amount Cash dividends paid Payments of Ordinary Dividends, Common Stock SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] Change in plan assets and benefit obligations recognized in AOCI, pre-tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract] Foreign currency translation (losses) gains during period, pre-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Stock Issued During Period, Value, Conversion of Convertible Securities Stock Issued During Period, Value, Conversion of Convertible Securities Equity securities Equity Securities [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Liability balance at December 31, 2019 Liability balance at December 31, 2020 Restructuring Reserve Stock issued during period, shares, share-based compensation (gross) Shares Issued, Shares, Share-based Payment Arrangement, before Forfeiture Entity Address, Postal Zip Code Entity Address, Postal Zip Code Total deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Fair value hedges, pre-tax benefit (expense) Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge Restructuring Type [Axis] Restructuring Type [Axis] Goodwill Goodwill, beginning balance Goodwill, ending balance Goodwill Proceeds from sale of intangible assets Proceeds from Sale of Intangible Assets 2.050% Notes (3) Notes 2.050% Due 2024 [Member] Notes 2.050% Due 2024 [Member] Net operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Impairment of long-lived and intangible assets (see Note 6) Restructuring Costs and Asset Impairment Charges Other Assets, Current Other Assets, Current Building and Building Improvements Building and Building Improvements [Member] Adjustment to LIFO Inventory, LIFO Reserve Schedule of the Changes in the Carrying Value of Goodwill by Reportable Segment Schedule of Goodwill [Table Text Block] Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Equity [Abstract] Equity [Abstract] 2022 Lessee Operating and Financing Lease, Liability, to be Paid, Year Two Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Assets and Liabilities Held for Sale Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Granted (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Entities [Table] Entities [Table] Customer Concentration Risk Customer Concentration Risk [Member] Reclassification to earnings, tax (expense) benefit Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Prepaid Expenses and Other Prepaid Expenses and Other Prepaid Expenses and Other Total weighted-average shares—diluted (shares) Weighted Average Number of Shares Outstanding, Diluted Derivative Contract [Domain] Derivative Contract [Domain] Schedule of Amortization Expense, for the Next Five Years Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Other current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Other Income and Expenses [Abstract] Other Income and Expenses [Abstract] Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Debt Disclosure [Abstract] Debt Disclosure [Abstract] Pirate Brands [Abstract] Pirate Brands [Abstract] Pirate Brands [Abstract] Restructuring Plan [Axis] Restructuring Plan [Axis] Current portion of long-term debt, fair value Long-term Debt, Current Maturities, Fair Value Long-term Debt, Current Maturities, Fair Value Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Repayment of long-term debt and finance leases Repayments of Long-term Debt Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Schedule of Outstanding Stock Options Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Balance at beginning of year Balance at end of year Unrecognized Tax Benefits Counterparty Name [Axis] Counterparty Name [Axis] Common stock Common Stock, Value, Issued 2024 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Document Fiscal Year Focus Document Fiscal Year Focus Global all-cap Global all-cap [Member] Equity Security which comprises equity funds that the MSCI World index. 2022 Finite-Lived Intangible Asset, Expected Amortization, Year Two SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] Current portion of long-term debt Less—current portion Long-term Debt, Current Maturities Projected benefit obligation at beginning of year Projected benefit obligation at end of year Defined Benefit Plan, Benefit Obligation Settlements Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Entity Current Reporting Status Entity Current Reporting Status Restructuring and related cost, expected cost Restructuring and Related Cost, Expected Cost Total comprehensive income including noncontrolling interest Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Derivative Instruments Derivatives and Fair Value [Text Block] Business Acquisition, Share Price Business Acquisition, Share Price Common stock, shares issued (shares) Common Stock, Shares, Issued Number Outstanding as of 12/31/20 (shares) Share-based Payment Arrangement, Option, Exercise Price Range, Shares Outstanding Total operating lease liabilities Operating Lease, Liability Net deferred tax liabilities Deferred Tax Liabilities, Net Long-term portion Long-term Debt, Excluding Current Maturities Segment Reporting [Abstract] Segment Reporting [Abstract] Debt Instrument [Line Items] Debt Instrument [Line Items] Total—The Hershey Company stockholders’ equity Stockholders' Equity Attributable to Parent Business Combination, Consideration Transferred Business Combination, Consideration Transferred 2.450% Notes (3) Notes 2.450% Due 2029 [Member] Notes 2.450% Due 2029 [Member] 2024 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Four Entity Address, City or Town Entity Address, City or Town Payroll, compensation and benefits Employee-related Liabilities, Current Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Other Assets, Noncurrent [Abstract] Other Assets, Noncurrent [Abstract] Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year 2025 Lessee, Operating Lease, Liability, to be Paid, Year Five Other assets Other Assets [Member] Total earnings—basic Allocation of total earnings used in basic computation Participating Securities, Distributed and Undistributed Earnings (Loss), Basic 3.375% Notes Notes 3.375% Due 2046 [Member] Notes 3.375% Due 2046 [Member] U.S. tax reform Effective Income Tax Rate Reconciliation, Tax Settlement, Domestic, Percent Amplify Snack Brands, Inc [Abstract] Amplify Snack Brands, Inc [Abstract] Amplify Snack Brands, Inc [Abstract] Net actuarial (loss) gain and prior service cost, tax (expense) benefit Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Gain (loss) on disposition of property plant equipment Gain (Loss) on Disposition of Property Plant Equipment Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Lease ROU assets Deferred Tax Liabilities, Leasing Arrangements Valuation allowance Deferred Tax Assets, Valuation Allowance Total lease payments Lessee Operating and Financing Lease Liability Payments Due Amount of lessee's undiscounted obligation for lease payments for operating and finance leases. Currency translation and other Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss) 2023 Finite-Lived Intangible Asset, Expected Amortization, Year Three Finance lease liabilities, non-current Finance Lease, Liability, Noncurrent Investment, Name [Domain] Investment, Name [Domain] Total other comprehensive (loss) income, after-tax amount Other Comprehensive Income (Loss), Net of Tax Leases [Abstract] Leases [Abstract] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Total current assets Assets, Current Comprehensive loss attributable to noncontrolling interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Earnings Per Share [Abstract] Earnings Per Share [Abstract] Deferred performance stock units, deferred restricted stock units, and directors' fees and accumulated dividend amounts representing deferred stock units outstanding Deferred Compensation Arrangement with Individual, Shares Issued Business realignment costs Costs associated with business realignment activities (see Note 9) Restructuring Charges Schedule of Deferred Tax Asset and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] State income taxes, net of Federal income tax benefits Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Lease liabilities Deferred Tax Asset, Leasing Arrangements Amount of deferred tax asset attributable to taxable temporary differences from leasing arrangements. Disposal Group Name [Domain] Disposal Group Name [Domain] 2025 Finite-Lived Intangible Asset, Expected Amortization, Year Five Document Fiscal Period Focus Document Fiscal Period Focus Reclassification to earnings, after-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Table] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Table] Operation Optimization Program Operational Optimization Program [Member] Operational Optimization Program [Member] Pension benefits liabilities Liability, Defined Benefit Pension Plan, Noncurrent Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Confectionery and confectionery-based portfolio Confectionery and Confectionery-based Portfolio [Member] Confectionery and Confectionery-based Portfolio [Member] Schedule of Activity Relating to the Noncontrolling Interest Schedule of Stockholders Equity [Table Text Block] Entity Filer Category Entity Filer Category Finite-Lived Customer Relationships, Gross Finite-Lived Customer Relationships, Gross Common stock Common Stock [Member] Product and Service [Domain] Product and Service [Domain] Foreign rate differences Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Defined Contribution Plan, Cost Defined Contribution Plan, Cost Inventories Deferred Tax Liabilities, Inventory Geographic Concentration Risk Geographic Concentration Risk [Member] Finance leases, Weighted-average remaining discount rate Finance Lease, Weighted Average Discount Rate, Percent McLane Company, Inc. McLane Company, Inc. [Member] McLane Company, Inc. [Member] 2021 Unrecorded Unconditional Purchase Obligation, to be Paid, Year One Amounts recognized in the Consolidated Balance Sheets: Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Increase (decrease) in cash and cash equivalents, including cash classified as held for sale Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect and Cash Classified as Held for Sale Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect and Cash Classified as Held for Sale Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) [Member] Interest rate, stated percentage Debt Instrument, Interest Rate, Stated Percentage Schedule of Accumulated Benefit Obligations in Excess of Plan Assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block] Margin for Growth Program Margin for Growth Program [Member] Margin for Growth Program [Member] Net income per share—diluted: Earnings Per Share, Diluted [Abstract] Exercised (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Reclassification of tax effects relating to U.S. tax reform, after-tax amount Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax Pension and Post-retirement Benefit Plans Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax Pension and Post-retirement Benefit Plans Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Nonoperating Income (Expense) Nonoperating Income (Expense) Employee stock options Share-based Payment Arrangement, Option [Member] Unsettled Accrued Liabilities Unsettled Accrued Liabilities Unsettled Accrued Liabilities Finite-Lived Noncompete Agreements, Gross Finite-Lived Noncompete Agreements, Gross 7.200% Debentures Debentures 7.2% Due 2027 [Member] Debentures 7.2% Due 2027 [Member] Treasury stock, shares (shares) Treasury stock, shares, beginning of the period (shares) Treasury stock, shares, end of the period (shares) Treasury Stock, Shares Foreign currency translation (losses) gains during period, after-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Number of Defined Benefit Other Post-retirement Plans and Defined Contribution Other Post-retirement Plans Number of Defined Benefit Other Post-retirement Plans and Defined Contribution Other Post-retirement Plans Number of Defined Benefit Other Post-retirement Plans and Defined Contribution Other Post-retirement Plans State Deferred State and Local Income Tax Expense (Benefit) Severance Employee Severance [Member] Ownership [Domain] Ownership [Domain] 2025 Long-Term Debt, Maturity, Year Five Expected long-term return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Domestic Income (Loss) from Continuing Operations before Income Taxes, Domestic Gain on sale of other assets Gain (Loss) on Disposition of Intangible Assets Entity number of part-time employees Entity Number of Part-Time Employees Entity Number of Part-Time Employees Long-term Debt, Fiscal Year Maturity [Abstract] Long-term Debt, Fiscal Year Maturity [Abstract] Total stockholders’ equity Beginning balance, stockholders' equity Ending balance, stockholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Additional paid-in capital Additional Paid in Capital Net sales Revenues 2021 Finite-Lived Intangible Asset, Expected Amortization, Year One Class of Stock [Axis] Class of Stock [Axis] Income taxes paid Income Taxes Paid, Net Proceeds from sales of businesses, net of cash and cash equivalents divested Proceeds from sales of businesses, net of cash and cash equivalents divested Proceeds from Divestiture of Businesses Accelerated depreciation and amortization Accelerated Depreciation and Amortization [Member] Accelerated Depreciation and Amortization [Member] (Losses) gains on cash flow hedging derivatives, tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Accrued liabilities Total accrued liabilities Accrued Liabilities, Current Net income per share - diluted (USD per share) Earnings Per Share—diluted (USD per share) Earnings Per Share, Diluted Schedule of Segment Information by Geography Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Schedule of Unrecognized Tax Benefits Roll Forward Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Goodwill and Other Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Plant, property and equipment, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment Schedule of Long-term Debt Instruments Schedule of Long-term Debt Instruments [Table Text Block] Depreciation Depreciation Entity Address, Address Line One Entity Address, Address Line One Noncompete Agreements Noncompete Agreements [Member] Entity Emerging Growth Company Entity Emerging Growth Company Indefinite-lived intangible assets, excluding goodwill Indefinite-lived Intangible Assets (Excluding Goodwill) Deferred Income Tax Expense (Benefit), Total Deferred Income Tax Expense (Benefit) 1.700% Notes (2) Notes 1.700% Due 2030 [Member] Notes 1.700% Due 2030 Impairment of Long-Lived Assets to be Disposed of Impairment of Long-Lived Assets to be Disposed of Prepaid Expense and Other Assets, Current [Abstract] Prepaid Expense and Other Assets, Current [Abstract] Finite-lived intangible assets, accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Maximum Maximum [Member] Preferred stock, shares authorized (shares) Preferred Stock, Shares Authorized Amounts recognized in Accumulated Other Comprehensive Income (Loss), net of tax: Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract] Noncontrolling Interests in Subsidiaries Noncontrolling Interest [Member] Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Fair Value Measurements Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Business Acquisition, Equity Interests Received, Common Stock, Value Business Acquisition, Equity Interests Received, Common Stock, Value Business Acquisition, Equity Interests Received, Common Stock, Value Common Stock Dividends, Common Stock, Cash Schedule of Net Interest Expense Interest Income and Interest Expense Disclosure [Table Text Block] KRAVE Pure Foods, Inc. [Member] KRAVE Pure Foods, Inc. [Member] KRAVE Pure Foods, Inc. [Member] Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Repayment of tax receivable obligation Repayment of Tax Receivable Obligation Repayment of Tax Receivable Obligation Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] FAIR VALUE MEASUREMENTS [Abstract] FAIR VALUE MEASUREMENTS [Abstract] FAIR VALUE MEASUREMENTS [Abstract] Other Benefits  Other Postretirement Benefits Plan [Member] Trading Symbol Trading Symbol Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Fair Value, Net Asset (Liability) Fair Value, Net Asset (Liability) Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Gain (Loss) on Sale of Properties Gain (Loss) on Sale of Properties Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Entity Shell Company Entity Shell Company Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Restructuring and Related Cost, Expected Cost, Cash Portion Restructuring and Related Cost, Expected Cost, Cash Portion Restructuring and Related Cost, Expected Cost, Cash Portion Fair Value, Measurements, Recurring Fair Value, Recurring [Member] 2022 Finance Lease, Liability, to be Paid, Year Two Entity Public Float Entity Public Float Global diversified assets Global diversified assets [Member] Global diversified assets [Member] Document Type Document Type ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Other (income) expense, net Total Other Nonoperating Income (Expense) Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Retirement of treasury common stock (shares) Treasury Stock, Shares, Retired Treasury Common Stock Treasury Stock [Member] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Segments [Axis] Segments [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] Pension and Other Post-Retirement Benefit Plans Retirement Benefits [Text Block] Vested (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Accrued liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accrued Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accrued Liabilities Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Significant other unobservable inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Net actuarial (loss) gain and prior service cost, after-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] Derivative asset Derivative Asset Dividends paid per share: Dividends (including dividend equivalents): Dividends, Common Stock [Abstract] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table] SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table] Line of Credit Line of Credit [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Deferred income taxes Non-current deferred tax liabilities, net Deferred Income Tax Liabilities, Net Other intangibles Total other intangible assets Intangible Assets, Net (Excluding Goodwill) Capitalized interest Interest Costs Capitalized Adjustment Operating profit Operating profit Operating Income (Loss) Weighted- Average Exercise Price (USD per share) Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Repurchase of common stock Payments for Repurchase of Common Stock Share-based compensation arrangement by share-based payment award, award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Entity Address, State or Province Entity Address, State or Province Vested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Schedule of Defined Benefit Obligations, Plan Assets, and Funded Status Schedule of Defined Benefit Plans Disclosures [Table Text Block] Accounts payable Accounts Payable, Current Total other comprehensive (loss) income, pre-tax amount Other Comprehensive Income (Loss), before Tax Foreign Currency Translation Goodwill, Foreign Currency Translation Gain (Loss) Computer Software Internal Use Software, Policy [Policy Text Block] Reclassification of tax effects relating to U.S. tax reform, after-tax amount Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax, Cash Flow Hedges Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax, Cash Flow Hedges Retained earnings Retained Earnings (Accumulated Deficit) Operating lease ROU Assets Operating Lease, Right-of-Use Asset Property, plant and equipment, net Deferred Tax Liabilities, Property, Plant and Equipment Reclassification of tax effects relating to U.S. tax reform, pre-tax amount Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre Tax Effect, Cash Flow Hedges Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre Tax Effect, Cash Flow Hedges Hershey Trust Company Hershey Trust Company [Member] Hershey Trust Company [Member] Reclassification to earnings due to sale of businesses, pre-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, before Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, before Tax 2021 Finance Lease, Liability, to be Paid, Year One Stockholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Net losses (gains) on mark-to-market valuation of commodity derivative positions recognized in unallocated derivative losses (gains) Net Mark to Market Valuation of Certain Derivative Positions Recognized in Unallocated Derivative (Gains) Losses Changes in the values of derivative positions that is recorded in unallocated derivative (gains)/losses Customer [Axis] Customer [Axis] Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Hedging Designation [Domain] Hedging Designation [Domain] U.S. government/agency US Treasury and Government [Member] Net lease cost Lease, Cost Equity investments in tax credit qualifying partnerships Payments to Acquire Equity Method Investments Options exercisable as of December 31, 2020 (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Machinery and equipment Machinery and Equipment, Gross Other investing activities Payments for (Proceeds from) Other Investing Activities Domestic Plans Domestic Plan [Member] Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Construction in progress Construction in Progress, Gross Thereafter Long-Term Debt, Maturity, after Year Five Net sales Revenue from Contract with Customer, Excluding Assessed Tax Advertising expense Advertising Expense Settlement Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement Estimated values (USD per share) Market price of common stock throughout the quarter (USD per share) Share Price Conversion of Class B common stock to Common shares outstanding Incremental Common Shares Attributable to Dilutive Effect of Conversion of Common Stock Incremental Common Shares Attributable to Dilutive Effect of Conversion of Common Stock Business Acquisition [Axis] Business Acquisition [Axis] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Geographical [Domain] Geographical [Domain] Settlement loss Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Scenario, Forecast Forecast [Member] Foreign Deferred Foreign Income Tax Expense (Benefit) Diluted earnings per share: Earnings Per Share, Diluted, Two Class Method [Abstract] Other long-term liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Entity Voluntary Filers Entity Voluntary Filers Business Combination, Acquisition Related Costs Business Combination, Acquisition Related Costs Credit Facility [Axis] Credit Facility [Axis] Preferred stock, shares issued (shares) Preferred Stock, Shares Issued Land Land Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Business Combinations [Abstract] Business Combinations [Abstract] Retirement Plan Name [Domain] Retirement Plan Name [Domain] Prepaid advertising expense Prepaid Advertising Intrinsic value of share-based liabilities paid, combined with the fair value of shares vested (in millions of dollars) Share Based Compensation Arrangement By Share Based Payment Award Intrinsic Value Of Share Based Liabilities Paid Combined With Fair Value Of Shares Vested Intrinsic value of share-based liabilities paid, combined with the fair value of shares vested (in millions of dollars). Operating leases Lessee, Operating Lease, Liability, Payment, Due [Abstract] Revenue Recognition [Abstract] Revenue Recognition [Abstract] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Accumulated depreciation Accumulated Depreciation [Member] Accumulated Depreciation [Member] Options exercisable, weighted aver remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Selling, marketing and administrative Selling, General and Administrative Expenses [Member] Capitalized computer software, accumulated amortization Capitalized Computer Software, Accumulated Amortization Goodwill [Roll Forward] Goodwill [Roll Forward] Schedule of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Purchase Consideration Allocation to Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Cash flow hedges, net of tax AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax Repayments of Debt Repayments of Debt Inventories Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Supplemental Balance Sheet Information Supplemental Balance Sheet Disclosures [Text Block] Partnerships Qualifying For Tax Credits Partnerships Qualifying For Tax Credits [Member] Partnerships Qualifying For Tax Credits [Member] Alternative investments, including real estate, listed infrastructure and other Other Investments [Member] Common stock, conversion basis (shares) Deferred Compensation Arrangement with Individual, Conversion Basis Deferred Compensation Arrangement with Individual, Conversion Basis Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Other Liabilities, Noncurrent [Abstract] Other Liabilities, Noncurrent [Abstract] Percentage of LIFO inventory Percentage of LIFO Inventory Entity Central Index Key Entity Central Index Key Derivative Instrument [Axis] Derivative Instrument [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Schedule of Gross Carrying Amount and Accumulated Amortization for Each Major Class of Intangible Asset Schedule of Finite-Lived Intangible Assets [Table Text Block] Less: Increase in cash and cash equivalents classified as held for sale (see Note 8) Cash and Cash Equivalents Classified as Held for Sale Increase (Decrease) Cash and Cash Equivalents Classified as Held for Sale Increase (Decrease) Geographical [Axis] Geographical [Axis] Schedule of Information Pertaining to Fair Value of PSUs and RSUs Granted for Potential Future Distribution Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block] Charged to Other Accounts SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account Cash flow hedges: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Post-retirement benefits liabilities Liability, Other Postretirement Defined Benefit Plan, Noncurrent Segments [Domain] Segments [Domain] Derivative instruments Deferred Tax Assets, Derivative Instruments Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Deferred compensation derivatives Equity Swap [Member] 2024 Long-Term Debt, Maturity, Year Four Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Income Statement Location [Axis] Income Statement Location [Axis] Weighted- Average Remaining Contractual Life in Years  Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Remaining Contractual Term Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Treasury Stock Acquired, Average Cost Per Share Treasury Stock Acquired, Average Cost Per Share Total recognized in other comprehensive (income) loss, pre-tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Advertising, promotion and product allowances Accrued Marketing Costs, Current Federal Current Federal Tax Expense (Benefit) Derivative, notional amount Derivative, Notional Amount Amortization of Intangible Assets Amortization of Intangible Assets Line of Credit Facility [Table] Line of Credit Facility [Table] Derivative, Fair Value, Net Derivative, Fair Value, Net Segment Information Segment Reporting Disclosure [Text Block] Historic and solar tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent 2.650% Notes (2) Notes 2.650% Notes Due 2050 [Member] Notes 2.650% Notes Due 2050 2.625% Notes Notes 2.625% Due 2023 [Member] Notes 2.625% Due 2023 [Member] Operating cash flows from finance leases Finance Lease, Interest Payment on Liability Scenario [Axis] Scenario [Axis] Revenue from Contract with Customer Benchmark Revenue from Contract with Customer Benchmark [Member] Less: Imputed interest Lessee Operating and Fiannce Lease Liability Undiscounted Excess Amount Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating and finance leases. Pension Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Pensions Line Of Credit Facility, Accordion Feature Increase Limit Line Of Credit Facility, Accordion Feature Increase Limit Line Of Credit Facility, Accordion Feature Increase Limit $105.92 - $157.32 Exercise Price Range Three [Member] Exercise Price Range Three [Member] Title of 12(b) Security Title of 12(b) Security Reclassification to earnings due to sale of businesses, after-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, Net of Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment To Earnings, Realized upon Sale or Liquidation, Net of Tax Tax cuts and jobs act, reclassification from aoci to retained earnings, tax effect Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Tyrrells and Shanghai Golden Monkey (SGM) Tyrrells and Shanghai Golden Monkey (SGM) [Member] Tyrrells and Shanghai Golden Monkey (SGM) [Member] Other assets Assets for Plan Benefits, Defined Benefit Plan Accrued income taxes Accrued Income Taxes, Current Other non-current assets Other Miscellaneous Assets, Non-Current Other Miscellaneous Assets, Non-Current Description of Business and Basis of Presentation Business Description and Basis of Presentation [Text Block] Schedule of Maturity of Finance Lease Liabilities Finance Lease, Liability, Fiscal Year Maturity [Table Text Block] Impairment charge on reclassified assets Impairment Charge on Reclassified Assets Interest expense Interest Expense Schedule of Depreciation and Amortization Expense Included within Segment Income Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table Text Block] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Depreciation and amortization Depreciation, Depletion and Amortization Schedule of Components of Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Product and Service [Axis] Product and Service [Axis] Derivative liability, gross liabilities Derivative Liability, Cash Transfers Receivable (Payable), Change In Quoted Market Prices On The Last Day Of Trading Derivative Liability, Cash Transfers Receivable (Payable), Change In Quoted Market Prices On The Last Day Of Trading ONE Brands, LLC ONE Brands, LLC [Member] ONE Brands, LLC [Member] Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition 2025 Finance Lease, Liability, to be Paid, Year Five Other program costs Other Restructuring [Member] Other Non-US [Member] 2022 Long-Term Debt, Maturity, Year Two Finite-Lived Trademarks, Gross Finite-Lived Trademarks, Gross Reclassification of tax effects relating to U.S. tax reform, tax (expense) benefit Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect, Cash Flow Hedges Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect, Cash Flow Hedges Reallocation of total earnings as a result of conversion of Class B common stock to Common stock Distributed Earnings Thereafter Lessee Operating and Financing Lease, Liability, to be Paid, after Year Five Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). (Losses) gains on cash flow hedging derivatives, before tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Raw materials Inventory, Raw Materials, Net of Reserves Dividends paid per share (USD per share) Common Stock, Dividends, Per Share, Cash Paid Debt Instrument [Axis] Debt Instrument [Axis] Fair Value Hedging Fair Value Hedging [Member] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Schedule of Quarterly Financial Information Quarterly Financial Information [Table Text Block] Operating Segments Operating Segments [Member] Class of Stock [Line Items] Class of Stock [Line Items] Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Derivative liability Derivative Liability Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Long-term debt, fair value Long-term Debt, Excluding Current Maturities, Fair Value Long-term Debt, Excluding Current Maturities, Fair Value Other non-current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets Entity Information [Line Items] Entity Information [Line Items] 4.125% Notes (1) Notes 4.125% Due 2020 [Member] Notes 4.125% Due 2020 [Member] Number Exercisable as of 12/31/20 (shares) Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable Research and development costs Research and Development Expense Projected benefit obligation Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Concentration Risk Type [Axis] Concentration Risk Type [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Lotte Shanghai Food Company Lotte Shanghai Food Company [Member] Lotte Shanghai Food Company [Member] Operating lease liabilities, non-current, extensible list Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] Revenue Recognition Revenue [Policy Text Block] Prepaid Expense Prepaid Expense Operating lease liabilities, non-current Operating Lease, Liability, Noncurrent 2024 Finite-Lived Intangible Asset, Expected Amortization, Year Four Other intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Net prior service credit (cost) Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax Customer relationship and trademark Customer Relationship and Trademark [Member] Customer Relationship and Trademark [Member] Tax contingencies Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Current assets: Assets, Current [Abstract] Interest income Investment Income, Interest Goodwill, gross Goodwill, Gross Derivative, Gain (Loss) on Derivative, Net Cumulative Amount of Mark-to-Market Gaines (Losses) on Commodity Derivatives Cumulative Amount of Mark-to-Market Gaines (Losses) on Commodity Derivatives Comprehensive income attributable to The Hershey Company Comprehensive Income (Loss), Net of Tax, Attributable to Parent 2023 Finance Lease, Liability, to be Paid, Year Three Dividend yields Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Patents Patents [Member] Preferred stock, par (USD per share) Preferred Stock, Par or Stated Value Per Share Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] 2021 Long-Term Debt, Maturity, Year One Rate of increase in compensation levels Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Deductions from Reserves SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction City Area Code City Area Code Document Period End Date Document Period End Date 2023 Unrecorded Unconditional Purchase Obligation, to be Paid, Year Three Operating lease liabilities, current, extensible list Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] Net income including noncontrolling interest Net income including noncontrolling interest Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Stock Repurchased During Period, Value Stock Repurchased During Period, Value Schedule of Stock Compensation Costs Share-based Payment Arrangement, Cost by Plan [Table Text Block] 3.125% Notes (3) Notes 3.125% Due 2049 [Member] Notes 3.125% Due 2049 [Member] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Stock-based compensation expense Share-based Payment Arrangement, Noncash Expense Net increase (decrease) in short-term debt Proceeds from (Repayments of) Short-term Debt Cover [Abstract] Cover [Abstract] Accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Other comprehensive income (loss) Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Schedule of Income (Loss) Before Income Taxes Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Total long-term debt Total long-term debt, carrying value Long-term Debt Leases Lessee, Operating Leases [Text Block] Retirement Plan Name [Axis] Retirement Plan Name [Axis] Fixed income securities Debt Securities [Member] Service cost Defined Benefit Plan, Service Cost Schedule of Other (Income) Expense, Net Other Income and Other Expense Disclosure [Text Block] Accrued income taxes Increase (Decrease) in Accrued Taxes Payable Customer Relationships Customer Relationships [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Cost of sales Cost of Goods and Services Sold Equity Components [Axis] Equity Components [Axis] $96.66 - $105.91 Exercise Price Range Two [Member] Exercise Price Range Two [Member] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Gross deferred tax assets Deferred Tax Assets, Gross Minimum Minimum [Member] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Write-down of equity investments Equity Method Investment, Other than Temporary Impairment Tax Cuts and Jobs Act of 2017, measurement period adjustment, income tax expense (benefit) Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit) Accumulated benefit obligation Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Net income (loss) attributable to noncontrolling interests Net income (loss) attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Amortization of net loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) Entity Interactive Data Current Entity Interactive Data Current United States UNITED STATES Total net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Exercises (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Schedule of Allocation of Plan Assets Schedule of Allocation of Plan Assets [Table Text Block] Workforce Subject to Collective Bargaining Arrangements Workforce Subject to Collective Bargaining Arrangements [Member] Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Equity and Noncontrolling Interest Stockholders' Equity Note Disclosure [Text Block] Schedule of Activity Relating to the Grants of Stock Options Share-based Payment Arrangement, Option, Activity [Table Text Block] Included in: Components of Deferred Tax Assets and Liabilities [Abstract] Commodities futures and options Commodity Contract [Member] Foreign Current Foreign Tax Expense (Benefit) Derivative [Table] Derivative [Table] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year One Total deferred tax liabilities Deferred Tax Liabilities, Gross Proceeds from sales of property, plant and equipment and other long-lived assets Proceeds from Sale of Property, Plant, and Equipment Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Number of reportable segments (segment) Number of Reportable Segments Retirement Plan Type [Domain] Retirement Plan Type [Domain] Exercise Price Range [Axis] Exercise Price Range [Axis] Business Realignment Activities Restructuring, Impairment, and Other Activities Disclosure [Text Block] Charged to Costs and Expenses SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense Cash flow hedge gain (loss) to be reclassified within twelve months Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Consolidation Items [Axis] Consolidation Items [Axis] 8.800% Debentures Debentures 8.8% Due 2021 [Member] Debentures 8.8% Due 2021 [Member] Net actuarial (loss) gain and prior service cost, pre-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Non-designated Hedges Not Designated as Hedging Instrument [Member] Other Other Miscellaneous Liabilities, Non-Current Other Miscellaneous Liabilities, Non-Current Goodwill, Impairment Loss Goodwill, Impairment Loss Accounts receivable—trade, net Accounts Receivable, after Allowance for Credit Loss, Current Net amounts recognized in AOCI Pension and post-retirement benefit plans, net of tax Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Noncontrolling interest, ownership percentage by parent Noncontrolling Interest, Ownership Percentage by Parent Total lease payments Lessee, Operating Lease, Liability, to be Paid Other Deferred Tax Assets, Other Business realignment and impairment charges Effective Income Tax Rate Reconciliation, Nondeductible Expense, Restructuring Charges, Percent Cost of Sales Cost of Goods and Service [Policy Text Block] Business realignment charges Restructuring Charges [Member] Currency Translation Foreign Currency Transactions and Translations Policy [Policy Text Block] Trademarks Trademarks [Member] Cash payments Payments for Restructuring Document Transition Report Document Transition Report Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Significant other observable inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Reclassification of tax effects relating to U.S. tax reform, tax (expense) benefit Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect, Pension and Post-retirement Benefit Plans Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect, Pension and Post-retirement Benefit Plans Schedule of Assets and Liabilities Measured at Fair Value Fair Value Measurements, Nonrecurring [Table Text Block] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Conversion of stock Conversion of Stock, Shares Converted Amounts recognized in net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] 2023 Lessee Operating and Financing Lease, Liability, to be Paid, Year Three Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Axis] Performance and restricted stock units Performance Shares And Restricted Stock Units (RSU) [Member] Performance Shares And Restricted Stock Units (RSU) [Member] Credit Facility [Domain] Credit Facility [Domain] Net income per share - basic (USD per share) Earnings Per Share—basic (USD per share) Earnings Per Share, Basic Amount of unrecognized tax benefits that if recognized would affect the effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Expected term in years Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Entity File Number Entity File Number Corporate Debt Securities Debt Security, Corporate, US [Member] Curtailment credit Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment Other long-term liabilities Liability, Defined Benefit Plan, Noncurrent Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Operating leases, Weighted-average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Total Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] Pre-tax compensation expense Share-based Payment Arrangement, Expense Balance Sheet Location [Axis] Balance Sheet Location [Axis] 2021 Lessee Operating and Financing Lease, Liability, to be Paid, Year One Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Disposal Group Name [Axis] Disposal Group Name [Axis] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Document Annual Report Document Annual Report Commercial Paper Commercial Paper [Member] Aggregate intrinsic value of options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Related income tax benefit Share-based Payment Arrangement, Expense, Tax Benefit 2024 Finance Lease, Liability, to be Paid, Year Four Share based compensation arrangement, by share based payment award, equity instruments other than options, performance score, percentage Share Based Compensation Arrangement, By Share Based Payment Award, Equity Instruments Other Than Options, Performance Score, Percentage Share Based Compensation Arrangement, By Share Based Payment Award, Equity Instruments Other Than Options, Performance Score, Percentage Retirement Benefits [Abstract] Retirement Benefits [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Inventory, Net [Abstract] Inventory, Net [Abstract] Net assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Noncontrolling interest in subsidiary Balance, December 31, 2019 Balance, December 31, 2020 Stockholders' Equity Attributable to Noncontrolling Interest Weighted-average fair value at date of grant (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Short-term debt Short-term Debt Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Other Deferred Tax Liabilities, Other Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Capitalized software, net Capitalized Computer Software, Net International Optimization Program International Optimization Program [Member] International Optimization Program Interest Expense Interest Expense [Member] Accounts receivable—trade, net Increase (Decrease) in Accounts Receivable Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Total liabilities and stockholders’ equity Liabilities and Equity Buildings Buildings and Improvements, Gross Accumulated other comprehensive loss Total accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Income Taxes Income Tax Disclosure [Text Block] Expiration of statutes of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Operating lease cost Operating Lease, Cost Hedging Relationship [Axis] Hedging Relationship [Axis] Deferred tax liabilities: Deferred Tax Liabilities, Gross [Abstract] Undistributed earnings of foreign subsidiaries Undistributed Earnings of Foreign Subsidiaries Antidilutive securities excluded from computation of earnings per share (shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Current Income Tax Expense (Benefit), Total Current Income Tax Expense (Benefit) Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Finance leases, Weighted-average remaining lease term Finance Lease, Weighted Average Remaining Lease Term Additions for tax positions taken during the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Additions for tax positions taken during prior years Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Asset, Useful Life Equity Component [Domain] Equity Component [Domain] Post-retirement benefit obligations Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Schedule of Expected Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] Gross profit Gross profit Gross Profit Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] Property, plant and equipment, net Long-lived assets Property, plant and equipment, net Property, Plant and Equipment, Net Entity Tax Identification Number Entity Tax Identification Number Interest expense, net Interest Income (Expense), Nonoperating, Net Lease, Description [Table] Lessee, Lease, Description [Table] Currency translation and other Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) Stock Compensation Plans Share-based Payment Arrangement [Text Block] Interest rate swap agreements Interest Rate Contract [Member] Net income attributable to The Hershey Company Net income attributable to The Hershey Company Net Income (Loss) Attributable to Parent Changes in assets and liabilities, net of business acquisitions and divestitures: Increase (Decrease) in Operating Capital [Abstract] Global infrastructure Global infrastructure [Member] Global infrastructure [Member] Total leased liabilities Lease, Liability Lease, Liability Current Fiscal Year End Date Current Fiscal Year End Date Total finance lease liabilities Finance Lease, Liability Common stock, voting percentage Common Stock, Voting Percentage Common Stock, Voting Percentage Change in Common Stock due to retirement of treasury shares (shares) Common Stock, Change Due to Retirement of Treasury Stock Common Stock, Change Due to Retirement of Treasury Stock Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Long-lived and intangible asset impairment charges Goodwill and Intangible Asset Impairment Reclassification of tax effects relating to U.S. tax reform, pre-tax amount Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre Tax Effect, Pension and Post-retirement Benefit Plans Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre Tax Effect, Pension and Post-retirement Benefit Plans Entity number of employees Entity Number of Employees Thereafter Finance Lease, Liability, to be Paid, after Year Five Foreign Line of Credit Foreign Line of Credit [Member] Supplemental Disclosure Supplemental Cash Flow Information [Abstract] Stock issuances: Shares Granted or Issued, Share-based Payment Arrangement [Abstract] Current debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Debt Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Number of brand names Number Of Brand Names Number Of Brand Names Property, Plant and Equipment [Line Items] Capitalized Software [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Allowance for Trade Receivables SEC Schedule, 12-09, Allowance, Credit Loss [Member] Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Net amounts recognized in periodic benefit cost and AOCI Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax Total other comprehensive (loss) income, tax (expense) benefit Other Comprehensive Income (Loss), Tax Property, plant and equipment, gross Property, Plant and Equipment, Gross [Member] Property, Plant and Equipment, Gross [Member] Finite-lived intangible assets, gross Finite-Lived Intangible Assets, Gross Total leased assets Lease, Right-of-Use Asset Lease, Right-of-Use Asset Foreign currency translation (losses) gains during period, tax (expense) benefit Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment International and Other International and Other Segment [Member] International and Other Segment [Member] North America North America Segment [Member] North America Segment [Member] Hedging Relationship [Domain] Hedging Relationship [Domain] Finance Lease, Right-of-Use Asset Finance lease ROU assets, net Finance Lease, Right-of-Use Asset, after Accumulated Amortization Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Schedule of Maturity of Operating Lease Liabilities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Total weighted-average shares—basic (shares) Weighted Average Number of Shares Outstanding, Basic 2024 Lessee Operating and Financing Lease, Liability, to be Paid, Year Four Amount of lessee's undiscounted obligation for lease payment for operating and finance leases to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Risk-free interest rates Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Ownership [Axis] Ownership [Axis] Forfeited (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Cash Cash and cash equivalents Cash and Cash Equivalents [Member] Non-service cost components of net periodic benefit cost relating to pension and other post-retirement benefit plans Defined Benefit Plan, Non-Service Cost Defined Benefit Plan, Non-Service Cost Cash Flow Hedges Cash Flow Hedging [Member] 2.300% Notes Notes 2.30% Due 2026 [Member] Notes 2.30% Due 2026 [Member] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Reclassification to earnings, pre-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Actuarial loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Total long-term debt, fair value Long-term Debt, Fair Value Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Inventories Inventory, Policy [Policy Text Block] Provision for income taxes Total provision for income taxes Income Tax Expense (Benefit) Total earnings—diluted Participating Securities, Distributed and Undistributed Earnings (Loss), Diluted Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Property, Plant and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Schedule of Maturities of Long-term Debt Schedule of Maturities of Long-term Debt [Table Text Block] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Finance lease liabilities, curent Finance Lease, Liability, Current Local Phone Number Local Phone Number $34.89 - $157.32 Exercise Price Range Four [Member] Exercise Price Range Four [Member] Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Domain] Intrinsic value of options exercised (in millions of dollars) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Derivative [Line Items] Derivative [Line Items] Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit Share-based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit Reductions for tax positions taken during prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Schedule II - Valuation and Qualifying Accounts SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] Exercise of stock options and incentive-based transactions Stock Issued During Period, Value, Stock Options Exercised Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Reclassification to earnings, tax (expense) benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Selling, Marketing and Administrative Expense Selling, General and Administrative Expenses, Policy [Policy Text Block] Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Award Type [Axis] Award Type [Axis] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Retained Earnings Retained Earnings [Member] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Schedule of Components of Net Periodic Benefit Cost Schedule of Net Benefit Costs [Table Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Schedule of Supplemental Cash Flow Information Related To Leases Schedule of Supplemental Cash Flow Information Related To Leases [Text Block] Schedule of supplemental cash flow information related to leases. Options outstanding, weighted-average remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Award Type [Domain] Award Type [Domain] Snacks portfolio Snacks Portfolio [Member] Snacks Portfolio [Member] Accrued liabilities Liability, Defined Benefit Plan, Current Schedule of Liability Activity for Costs Qualifying as Exit and Disposal Costs Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Options exercisable (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Schedule of Other Fair Value Measurements Schedule of Impaired Intangible Assets [Table Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Treasury—common stock shares, at cost: 13,325,898 in 2020 and 12,723,592 in 2019 Treasury Stock, Value Facility Closing Facility Closing [Member] Earnings Per Share Earnings Per Share [Text Block] Pension Benefits  Pension Plan [Member] Discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Other, net Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Current liabilities: Liabilities, Current [Abstract] Federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Contributions to pension and other benefit plans Payment for Pension and Other Postretirement Benefits Income Tax Contingency [Table] Income Tax Contingency [Table] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Net income per share—basic: Earnings Per Share, Basic [Abstract]