Commitments and Contingencies Disclosure [Abstract] Contingencies Commitments and Contingencies Disclosure [Text Block] Retirement Benefits [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension Benefits Pension Plan [Member] Other Benefits Other Postretirement Benefits Plan [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Defined Benefit Plan, Remeasurement, Basis Spread on Discount Rate Defined Benefit Plan, Remeasurement, Basis Spread on Discount Rate Defined Benefit Plan, Remeasurement, Basis Spread on Discount Rate Expected return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Debt Disclosure [Abstract] Line of Credit Facility [Table] Line of Credit Facility [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Line of Credit Line of Credit [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility Revolving Credit Facility [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Foreign Line of Credit Foreign Line of Credit [Member] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Commercial Paper Commercial Paper [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Line of credit facility, accordion feature increase limit Line Of Credit Facility, Accordion Feature Increase Limit Line Of Credit Facility, Accordion Feature Increase Limit Short-term foreign bank loans against the lines of credit Line of Credit, Current Short-term debt Short-term Debt Short-term debt, weighted average interest rate Short-term Debt, Weighted Average Interest Rate, at Point in Time Fair Value Disclosures [Abstract] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Foreign exchange contracts Foreign Exchange Contract [Member] Interest rate swap agreements Interest Rate Contract [Member] Deferred compensation derivatives Equity Swap [Member] Commodities futures and options Commodity Contract [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Quoted prices in active markets of identical assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant other observable inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant other unobservable inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Derivative asset Derivative Asset Derivative liability Derivative Liability Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] North America North America Segment [Member] North America Segment [Member] International and Other International and Other Segment [Member] International and Other Segment [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill, beginning balance Goodwill Acquired during the period Goodwill, Acquired During Period Purchase price allocation adjustment Goodwill, Purchase Accounting Adjustments Divested during the period Goodwill, Written off Related to Sale of Business Unit Foreign currency translation and other Goodwill, Foreign Currency Translation Gain (Loss) Goodwill, ending balance Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Amplify Snack Brands, Inc. Amplify Snack Brands, Inc. [Member] Amplify Snack Brands, Inc. [Member] Business Acquisition and Divestitures [Line Items] Business Acquisition [Line Items] Schedule of Purchase Consideration Allocation to Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Business Acquisition [Line Items] Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Plant, property and equipment, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment Goodwill Other intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Other non-current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets Accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable 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 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 Other current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Non-current deferred income taxes Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent Non-current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Net assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Statement of Cash Flows [Abstract] Net income including noncontrolling interest Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] 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] Depreciation and amortization Depreciation, Depletion and Amortization Stock-based compensation expense Share-based Compensation Deferred income taxes Deferred Income Taxes and Tax Credits Impairment of long-lived assets Restructuring Costs and Asset Impairment Charges Write-down of equity investments Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net Other Other Operating Activities, Cash Flow Statement Changes in assets and liabilities, net of business acquisition and divestitures: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable—trade, net Increase (Decrease) in Accounts Receivable Inventories Increase (Decrease) in Inventories Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Accrued income taxes Increase (Decrease) in Accrued Taxes Payable Contributions to pension and other benefit plans Payment for Pension and Other Postretirement Benefits Other assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Capital additions (including software) Payments to Acquire Property, Plant, and Equipment Proceeds from sales of property, plant and equipment and other long-lived assets Proceeds from Sale of Property, Plant, and Equipment Proceeds from sales of businesses, net of cash and cash equivalents divested Proceeds from Divestiture of Businesses Equity investments in tax credit qualifying partnerships Payments to Acquire Equity Method Investments Business acquisition, net of cash and cash equivalents acquired Payments to Acquire Businesses, Net of Cash Acquired Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Net increase in short-term debt Proceeds from (Repayments of) Short-term Debt Long-term borrowings Proceeds from Issuance of Long-term Debt Repayment of long-term debt Repayments of Long-term Debt Repayment of tax receivable obligation Repayment of Tax Receivable Obligation Repayment of Tax Receivable Obligation Cash dividends paid Payments of Ordinary Dividends, Common Stock Repurchase of common stock Payments for Repurchase of Common Stock Exercise of stock options Proceeds from Stock Options Exercised Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period Supplemental Disclosure Supplemental Cash Flow Information [Abstract] Interest paid Interest Paid, Net Income taxes paid Income Taxes Paid, Net Organization, Consolidation and Presentation of Financial Statements [Abstract] Schedule of Supplemental Balance Sheet Information Schedule of Supplemental Balance Sheet Information [Table Text Block] Schedule of Supplemental Balance Sheet Information [Table Text Block] Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Pirate Brands Pirate Brands [Member] Pirate Brands [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Scenario, Forecast Scenario, Forecast [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Net sales Revenue, Net Consideration transferred Business Combination, Consideration Transferred Amounts recognized in net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Amortization of prior service (credit) cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Amortization of net loss Defined Benefit Plan, Amortization of Gain (Loss) Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment Total net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Derivative Instruments and Hedging Activities Disclosure [Abstract] 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] Schedule of the Effect of Derivative Instruments on the Consolidated Statements of Income Derivative Instruments, Gain (Loss) [Table Text Block] Restructuring and Related Activities [Abstract] Schedule of Business Realignment Activity Restructuring and Related Costs [Table Text Block] Schedule of Liability Activity for Costs Qualifying as Exit and Disposal Costs Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship Hedging Relationship [Domain] Cash Flow Hedges Cash Flow Hedging [Member] Fair Value Hedging Fair Value Hedging [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Non-designated Hedges Not Designated as Hedging Instrument [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] 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 Derivative Asset, 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 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 Schedule of Components of Net Periodic Benefit Cost Schedule of Net Benefit Costs [Table Text Block] FAIR VALUE MEASUREMENTS [Abstract] FAIR VALUE MEASUREMENTS [Abstract] Schedule of Assets and Liabilities Measured at Fair Value Fair Value Measurements, Nonrecurring [Table Text Block] 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] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Corporate Debt Securities Domestic Corporate Debt Securities [Member] 1.60% Notes due 2018 (1) Notes 1.60% Due 2018 [Member] Notes 1.60% Due 2018 [Member] 2.90% Notes Due 2020 Notes 2.90% Due 2020 [Domain] Notes 2.90% Due 2020 4.125% Notes due 2020 Notes 4.125% Due 2020 [Member] Notes 4.125% Due 2020 [Member] 3.10% Notes Due 2021 Notes 3.10% Due 2021 [Domain] Notes 3.10% Due 2021 8.8% Debentures due 2021 Debentures 8.8% Due 2021 [Member] Debentures 8.8% Due 2021 [Member] 3.375% Notes Due 2023 Notes 3.375% Due 2023 [Domain] Notes 3.375% Due 2023 2.625% Notes due 2023 Notes 2.625% Due 2023 [Member] Notes 2.625% Due 2023 [Member] 3.20% Notes due 2025 Notes 3.20% Due 2025 [Member] Notes 3.20% Due 2025 [Member] 2.30% Notes due 2026 Notes 2.30% Due 2026 [Member] Notes 2.30% Due 2026 [Member] 7.2% Debentures due 2027 Debentures 7.2% Due 2027 [Member] Debentures 7.2% Due 2027 [Member] 3.375% Notes due 2046 Notes 3.375% Due 2046 [Member] Notes 3.375% Due 2046 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Interest rate, stated percentage Debt Instrument, Interest Rate, Stated Percentage Business Realignment Activities Restructuring, Impairment, and Other Activities Disclosure [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] 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] Outstanding shares at beginning of year (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercised (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Outstanding as of September 30, 2018 (shares) Options exercisable as of September 30, 2018 (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number 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] Outstanding (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercises (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Outstanding (USD per share) Options exercisable (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Options outstanding, weighted-average remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Options exercisable, weighted aver remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate intrinsic value of options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate intrinsic value of options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Derivative [Table] Derivative [Table] Derivative [Line Items] Derivative [Line Items] Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Gains (losses) recognized in other comprehensive income (“OCI”) (effective portion) Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Gains (losses) reclassified from accumulated OCI into income (effective portion) Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Tyrrells and Shanghai Golden Monkey (SGM) Tyrrells and Shanghai Golden Monkey (SGM) [Member] Tyrrells and Shanghai Golden Monkey (SGM) [Member] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Operational Optimization Program China Structure Optimization [Member] China Structure Optimization [Member] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Facility Closing Facility Closing [Member] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Licensing Rights Licensing Agreements [Member] 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] Proceeds from sale of intangible assets Proceeds from Sale of Intangible Assets Gain (loss) on disposition of intangible assets Gain (Loss) on Disposition of Intangible Assets Gain (loss) on disposition of property plant equipment Gain (Loss) on Disposition of Property Plant Equipment Long-lived asset impairment charges Asset Impairment Charges Long-lived assets Disposal Group, Including Discontinued Operations, Long-lived Assets Disposal Group, Including Discontinued Operations, Long-lived Assets Non-current assets Disposal Group, Including Discontinued Operation, Assets, Noncurrent Assets Disposal Group, Including Discontinued Operation, Assets Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common stock Hershey Common Stock [Member] Hershey Common Stock [Member] Class B common stock Common Class B [Member] Statement [Line Items] Statement [Line Items] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Accounts receivable—trade, net Accounts Receivable, Net, Current Inventories Inventory, Net Prepaid expenses and other Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property, plant and equipment, net Property, Plant and Equipment, Net Other intangibles Intangible Assets, Net (Excluding Goodwill) Other assets Other Assets, Noncurrent Deferred income taxes Deferred Tax Assets, Net, Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued liabilities Accrued Liabilities, Current Accrued income taxes Accrued Income Taxes, Current Current portion of long-term debt Long-term Debt, Current Maturities Total current liabilities Liabilities, Current Long-term debt Long-term Debt and Capital Lease Obligations Other long-term liabilities Other Liabilities, Noncurrent Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Total liabilities Liabilities Stockholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Preferred stock, shares issued: none at September 30, 2018 and December 31, 2017 Preferred Stock, Value, Issued Common stock Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Treasury—common stock shares, at cost: 150,181,170 at September 30, 2018 and 149,040,927 at December 31, 2017 Treasury Stock, Value Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total—The Hershey Company stockholders’ equity Stockholders' Equity Attributable to Parent Noncontrolling interest in subsidiary Stockholders' Equity Attributable to Noncontrolling Interest Total stockholders’ equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and stockholders’ equity Liabilities and Equity Other Income and Expenses [Abstract] Other (Income) Expense, Net Schedule of Other Nonoperating Income (Expense) [Table Text Block] Segment Reporting [Abstract] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of Sales Cost of Sales [Member] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Geographic Concentration Risk Geographic Concentration Risk [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Sales Revenue, Goods, Net Sales Revenue, Goods, Net [Member] Revenue, Major Customer [Line Items] Revenue, Major Customer [Line Items] Concentration Risk, Percentage Concentration Risk, Percentage Derivative, Gain (Loss) on Derivative, Net Cumulative Amount of Mark-to-Market Losses on Commodity Derivatives Cumulative Amount of Mark-to-Market Losses on Commodity Derivatives Net Gain Loss On Commodity Derivative Positions Reclassified From Unallocated Derivative Gains Losses 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. Short and Long-Term Debt Debt Disclosure [Text Block] Schedule of Stock Compensation Costs Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Schedule of Activity Relating to the Grants of Stock Options Share-based Compensation, Stock Options, Activity [Table Text Block] 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] Schedule of Activity Relating to Grants of PSUs and RSUs Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] 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] Equity [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] 2016 Share Repurchase Program 2016 Share Repurchase Program [Member] 2016 Share Repurchase Program [Member] 2017 Share Repurchase Program 2017 Share Repurchase Program [Member] 2017 Share Repurchase Program [Member] 2018 Share Repurchase Program 2018 Share Repurchase Program [Member] [Domain] 2018 Share Repurchase Program [Member] [Domain] Class of Stock [Line Items] Class of Stock [Line Items] Authorized stock repurchase amount Stock Repurchase Program, Authorized Amount Remaining authorized repurchase amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Assets Held for Sale Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Dividends paid per share (USD per share) Common Stock, Dividends, Per Share, Cash Paid Accounting Policies [Abstract] Schedule of New Accounting Pronouncements Changes Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Amortization of Intangible Assets Amortization of Intangible Assets Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Trademarks Trademarks [Member] Customer-related Customer-Related Intangible Assets [Member] Patents Patents [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Finite-lived intangible assets, gross Finite-Lived Intangible Assets, Gross Finite-lived intangible assets, accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Indefinite-lived intangible assets, excluding goodwill Indefinite-Lived Intangible Assets (Excluding Goodwill) Total other intangible assets Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Employee stock options Employee Stock Option [Member] Performance Stock Units and Restricted Stock Units [Member] Performance Stock Units and Restricted Stock Units [Member] Performance Stock Units and Restricted Stock Units [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Employee service share-based compensation, nonvested awards, compensation cost not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Weighted-average fair value of options granted (per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Intrinsic value of options exercised (in millions of dollars) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value 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). 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 Common stock, conversion basis (shares) Deferred Compensation Arrangement with Individual, Conversion Basis Deferred Compensation Arrangement with Individual, Conversion Basis Fair Value Measurements Fair Value, Measurement Inputs, Disclosure [Text Block] Schedule of Net Sales and Earnings by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Unallocated Mark-to-Market (Gains) Losses 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] Schedule of Depreciation and Amortization Expense Included within Segment Income Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table Text Block] Schedule of the Changes in the Carrying Value of Goodwill by Reportable Segment Schedule of Goodwill [Table Text Block] Schedule of Gross Carrying Amount and Accumulated Amortization for Each Major Class of Intangible Asset Schedule of Finite-Lived Intangible Assets [Table Text Block] Dividend yields Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Risk-free interest rates Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected term in years Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Supplemental Balance Sheet Information Supplemental Balance Sheet Disclosures [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Corporate, Non-Segment Corporate, Non-Segment [Member] Segment Reconciling Items Segment Reconciling Items [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Net Sales Operating Income (Loss) Operating Income (Loss) Derivative, Gain (Loss) on Derivative, Net Derivative, Gain (Loss) on Derivative, Net Goodwill and long-lived asset impairment charges Goodwill and Intangible Asset Impairment Costs associated with business realignment activities Restructuring Charges Acquisition-related costs Business Combination, Integration Related Costs Gain (loss) on disposition of intangible assets Interest expense, net Interest Income (Expense), Nonoperating, Net Other (income) expense, net Other Nonoperating Income (Expense) Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Treasury Stock Activity Stockholders' Equity Note Disclosure [Text Block] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Earnings Per Share [Abstract] Schedule of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Inventory, Net [Abstract] Raw materials Inventory, Raw Materials, Net of Reserves Goods in process Inventory, Work in Process, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Inventories at FIFO FIFO Inventory Amount Adjustment to LIFO Inventory, LIFO Reserve Total inventories Prepaid Expense and Other Assets, Current [Abstract] Prepaid Expense and Other Assets, Current [Abstract] Prepaid expenses Prepaid Expense Assets held for sale Other current assets Other Assets, Current Total prepaid expenses and other Prepaid Expenses and Other Prepaid Expenses and Other Property, Plant and Equipment [Abstract] Land Land Buildings Buildings and Improvements, Gross Machinery and equipment Machinery and Equipment, Gross Construction in progress Construction in Progress, Gross Property, plant and equipment, gross Property, Plant and Equipment, Gross Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, plant and equipment, net Other Assets, Noncurrent [Abstract] Capitalized software, net Capitalized Computer Software, Net Other non-current assets Other Miscellaneous Assets, Non-Current Other Miscellaneous Assets, Non-Current Total other assets Accrued Liabilities, Current [Abstract] Payroll, compensation and benefits Employee-related Liabilities, Current Advertising and promotion Accrued Marketing Costs, Current Other Other Accrued Liabilities, Current Total accrued liabilities Other Liabilities, Noncurrent [Abstract] Post-retirement benefits liabilities Liability, Other Postretirement Defined Benefit Plan, Noncurrent Pension benefits liabilities Liability, Defined Benefit Pension Plan, Noncurrent Other Other Miscellaneous Liabilities, Non-Current Other Miscellaneous Liabilities, Non-Current Total other long-term liabilities Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustments Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Pension and post-retirement benefit plans, net of tax Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Cash flow hedges, net of tax Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Total accumulated other comprehensive loss Interest expense Interest Expense, Debt Capitalized interest Interest Costs Capitalized Adjustment Interest expense Interest Expense Interest income Investment Income, Interest Interest expense, net Income Tax Disclosure [Abstract] Income Tax Contingency [Table] Income Tax Contingency [Table] Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Effective income tax rate reconciliation, at federal statutory income tax rate, percent Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective income tax rate reconciliation, percent Effective Income Tax Rate Reconciliation, Percent Significant change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Tax Cuts and Jobs Act of 2017, Net Impact Change in Tax Rate and Mandatory Tax on Unremitted Foreign Earnings, Income Tax Expense (Benefit) Tax Cuts and Jobs Act of 2017, Net Impact Change in Tax Rate and Mandatory Tax on Unremitted Foreign Earnings, Income Tax Expense (Benefit) Tax Cuts and Jobs Act of 2017, Net Impact Change in Tax Rate and Mandatory Tax on Unremitted Foreign Earnings, Income Tax Expense (Benefit) 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] Performance and restricted stock units Performance Shares And Restricted Stock Units (RSU) [Member] Performance Shares And Restricted Stock Units (RSU) [Member] 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] Basic earnings per share: Earnings Per Share, Basic, Two Class Method [Abstract] Allocation of distributed earnings (cash dividends paid) Dividends Allocation of undistributed earnings Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Total earnings—basic Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Total weighted-average shares—basic (shares) Weighted Average Number of Shares Outstanding, Basic Earnings Per Share—basic (USD per share) Earnings Per Share, Basic Diluted earnings per share: Earnings Per Share, Diluted, Two Class Method [Abstract] Allocation of total earnings used in basic computation Reallocation of total earnings as a result of conversion of Class B common stock to Common stock Distributed Earnings Reallocation of undistributed earnings Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted Total earnings—diluted Participating Securities, Distributed and Undistributed Earnings (Loss), Diluted 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 Incremental common shares attributable to dilutive effect of share-based payment arrangements Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Total weighted-average shares—diluted (shares) Weighted Average Number of Shares Outstanding, Diluted Earnings Per Share—diluted (USD per share) Earnings Per Share, Diluted Statement of Comprehensive Income [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Pension and post-retirement benefit plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Cash flow hedges Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustments, pre-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Foreign currency translation adjustments, tax (expense) benefit Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Foreign currency translation adjustments, after-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Reclassification to earning due to the sale of businesses, pre-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax Reclassification to earning due to the sale of businesses, tax (expense) benefit Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Tax Reclassification to earning due to the sale of businesses, after-tax amount Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax Pension and post-retirement benefit plans: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract] Net actuarial gain (loss) and prior service cost, pre-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Net actuarial gain (loss) and prior service cost, tax (expense) benefit Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Net actuarial gain (loss) and prior service cost, after-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Tax cuts and jobs act, reclassification from aoci to retained earnings, pre tax effect Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre Tax Effect Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Pre 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 Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect Tax cuts and jobs act, reclassification from aoci to retained earnings, after tax Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax Tax Cuts and Jobs Act, Reclassification From AOCI To Retained Earnings, After Tax Reclassification to earnings, pre-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Reclassification to earnings, tax (expense) benefit Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Reclassification to earnings, after-tax amount Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax Cash flow hedges: Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract] Gains (losses) on cash flow hedging derivatives, pre-tax amount Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax Gains (losses) on cash flow hedging derivatives, tax (expense) benefit Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Gains (losses) on cash flow hedging derivatives, after-tax amount Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Reclassification to earnings, pre-tax amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax Reclassification to earnings, tax (expense) benefit Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax Reclassification to earnings, after-tax amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Total other comprehensive income (loss), pre-tax amount Other Comprehensive Income (Loss), before Tax Total other comprehensive income (loss), tax (expense) benefit Other Comprehensive Income (Loss), Tax Total other comprehensive income (loss), after-tax amount Other Comprehensive Income (Loss), Net of Tax Total comprehensive income including noncontrolling interest Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income (loss) attributable to noncontrolling interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive income attributable to The Hershey Company Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Liability balance at December 31, 2017 Restructuring Reserve 2018 business realignment charges Restructuring Charges, Business Realignment Reserve Restructuring Charges, Business Realignment Reserve Cash payments Payments for Restructuring Other, net Restructuring Reserve, Accrual Adjustment Liability balance at September 30, 2018 Document And Entity Information [Abstract] Document Information [Table] Document Information [Table] Document Information [Line Items] Document Information [Line Items] Entity registrant name Entity Registrant Name Entity central index key Entity Central Index Key Current fiscal year end date Current Fiscal Year End Date Entity filer category Entity Filer Category Document type Document Type Document period end date Document Period End Date Document fiscal year focus Document Fiscal Year Focus Document fiscal period focus Document Fiscal Period Focus Amendment flag Amendment Flag Entity common stock, shares outstanding (shares) Entity Common Stock, Shares Outstanding Entity current reporting status Entity Current Reporting Status Entity public float Entity Public Float New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2017-07 Accounting Standards Update 2017-07 [Member] Accounting Standards Update 2017-07 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Cost of Goods Sold Cost of Goods Sold Selling, General and Administrative Expense Selling, General and Administrative Expense Other Nonoperating Income (Expense) Reclassification from AOCI to Retained Earnings Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings Noncontrolling Interest [Table] Noncontrolling Interest [Table] Ownership [Axis] Ownership [Axis] Ownership [Domain] Ownership [Domain] Lotte Shanghai Food Company [Member] Lotte Shanghai Food Company [Member] Lotte Shanghai Food Company [Member] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Noncontrolling Interest, Ownership Percentage by Parent Noncontrolling Interest, Ownership Percentage by Parent Schedule of Other (Income) Expense, Net Other Income and Other Expense Disclosure [Text Block] Schedule of Long-term Debt Instruments Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Net Interest Expense Interest Income and Interest Expense Disclosure [Table Text Block] Pension and Other Post-Retirement Benefit Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Severance Employee Severance [Member] Accelerated depreciation and amortization Accelerated Depreciation and Amortization [Member] Accelerated Depreciation and Amortization [Member] Other Program Costs Other Restructuring [Member] Margin for Growth Program Margin for Growth Program [Member] Margin for Growth Program [Member] Selling, marketing and administrative Selling, General and Administrative Expenses [Member] Business realignment charges Restructuring Charges [Member] Business realignment costs Noncontrolling Interests in Subsidiaries Noncontrolling Interest [Member] Balance, December 31, 2017 Net income (loss) attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest 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 Balance, September 30, 2018 Pre-tax compensation expense Allocated Share-based Compensation Expense Related income tax benefit Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Assets Held for Sale Disposal Groups, Including Discontinued Operations [Table Text Block] Corporate (1) Corporate Segment [Member] Segment Information Segment Reporting Disclosure [Text Block] Preferred Stock Preferred Stock [Member] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] Treasury Common Stock Treasury Stock [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance, stockholders' equity Net income attributable to The Hershey Company Net Income (Loss) Attributable to Parent Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Dividends (including dividend equivalents): Dividends, Common Stock [Abstract] Common Stock Dividends, Common Stock, Cash Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Exercise of stock options and incentive-based transactions Stock Issued During Period, Value, Stock Options Exercised Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Reclassification of tax effects relating to U.S. tax reform Ending balance, stockholders' equity Earnings Per Share Earnings Per Share [Text Block] Lease Obligations Capital Lease Obligations [Member] Total long-term debt Long-term Debt 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 Less—current portion Long-term portion Long-term Debt, Excluding Current Maturities Repayments of debt Repayments of Debt Proceeds from Issuance of Other Long-term Debt Proceeds from Issuance of Other Long-term Debt Minimum Minimum [Member] Maximum Maximum [Member] Customer Relationships Customer Relationships [Member] Payments to acquire businesses, gross Payments to Acquire Businesses, Gross Consideration transferred, per share of common stock Business Acquisition, Share Price Equity interests received, common stock, value Business Acquisition, Equity Interests Received, Common Stock, Value Business Acquisition, Equity Interests Received, Common Stock, Value Business combination, recognized identifiable assets acquired and liabilities assumed, cash and equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Finite-lived trademarks, gross Finite-Lived Trademarks, Gross Finite-lived customer relationships, gross Finite-Lived Customer Relationships, Gross Finite-lived intangible asset, useful life Finite-Lived Intangible Asset, Useful Life Acquisition related costs Business Combination, Acquisition Related Costs Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Schedule of Activity Relating to the Noncontrolling Interest Schedule of Stockholders Equity [Table Text Block] North America North America [Member] Restructuring and related cost, expected cost Restructuring and Related Cost, Expected Cost Restructuring and related cost, cost incurred to date Restructuring and Related Cost, Cost Incurred to Date Restructuring and related cost, expected cost remaining Restructuring and Related Cost, Expected Cost Remaining Effect on future cash flows, amount Effect on Future Cash Flows, Amount Restructuring and related cost, expected number of positions eliminated, percent Restructuring and Related Cost, Expected Number of Positions Eliminated, Percent Restructuring and Related Cost, Expected Number of Positions Eliminated, Percent Impairment of intangible assets (excluding goodwill) Impairment of Intangible Assets (Excluding Goodwill) Impairment of long-lived assets held-for-use Impairment of Long-Lived Assets Held-for-use Income Taxes Income Tax Disclosure [Text Block] Subsequent Event Subsequent Events [Text Block] Business Acquisition Mergers, Acquisitions and Dispositions Disclosures [Text Block] Income Statement [Abstract] Cost of sales Gross profit Gross Profit Selling, marketing and administrative expense Business realignment costs Restructuring Charges, Business Realignment Restructuring Charges, Business Realignment Operating profit Income before income taxes Provision for income taxes Income Tax Expense (Benefit) Net income including noncontrolling interest Net income (loss) attributable to noncontrolling interests Net income attributable to The Hershey Company Net income per share—basic: Earnings Per Share, Basic [Abstract] Net income per share - basic (USD per share) Net income per share—diluted: Earnings Per Share, Diluted [Abstract] Net income per share - diluted (USD per share) Dividends paid per share: Interest Rate Swap [Member] Interest Rate Swap [Member] Interest Expense Interest Expense [Member] Derivative, term of contract Derivative, Term of Contract Derivative, notional amount Derivative, Notional Amount 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. Maximum length of time, hedged in cash flow hedge Maximum Length of Time Hedged in Cash Flow Hedge Cash flow hedge gain (loss) to be reclassified within twelve months Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Fair value hedges, pre-tax benefit Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge Stock Compensation Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Derivative Instruments Derivatives and Fair Value [Text Block] Schedule of Treasury Stock Activity Schedule of Common Stock Outstanding Roll Forward [Table Text Block] Units granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 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 Estimated values (USD per share) Share Price Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Noncontrolling Interest Noncontrolling Interest Disclosure [Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive securities excluded from computation of earnings per share (shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Fair Value, Net Asset (Liability) Fair Value, Net Asset (Liability) Impairment of Long-Lived Assets to be Disposed of Impairment of Long-Lived Assets to be Disposed of Total share repurchases (in shares) Treasury Stock, Shares, Acquired Shares issued for stock options and incentive compensation (in shares) Stock Issued During Period, Shares, Share-based Compensation, Gross Net change (in shares) Treasury Stock Change in Shares Change in the number of common shares that were previously issued and that were repurchased by the issuing entity and held in treasury during the period. This stock has no voting rights and receives no dividends. Total share repurchases Stock Repurchased During Period, Value Shares issued for stock options and incentive compensation Stock Issued During Period, Value, Share-based Compensation, Gross Net change Treasury Stock Change in Value Change in value of common shares of an entity that were issued, repurchased by the entity, and are held in its treasury during the period. Treasury stock is issued but is not outstanding. This stock has no voting rights and receives no dividends. Note that treasury stock may be recorded at its total cost or separately as par (or stated) value and additional paid in capital. Note: number of treasury shares concept is in another section within stockholders' equity. Net Mark to Market Valuation of Certain Derivative Positions Recognized in Unallocated Derivative Gains Losses 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 Preferred stock, shares issued (shares) Preferred Stock, Shares Issued Common stock, shares issued (shares) Common Stock, Shares, Issued Treasury stock, shares (shares) Treasury Stock, Shares 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] Outstanding at beginning of year (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (shares) 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. Vested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Outstanding as of September 30, 2018 (shares) 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] Outstanding at beginning 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 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. 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 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 Outstanding as of September 30, 2018 (USD per share) Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] 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] Long-term Debt, Current Maturities, Fair Value Long-term Debt, Current Maturities, Fair Value Long-term Debt, Current Maturities, Fair Value Long-term Debt, Excluding Current Maturities, Fair Value Long-term Debt, Excluding Current Maturities, Fair Value Long-term Debt, Excluding Current Maturities, Fair Value Long-term Debt, Fair Value Long-term Debt, Fair Value Long-term Debt Write-down of equity investments in partnerships qualifying for tax credits Equity Method Investment, Other than Temporary Impairment 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 Other (income) expense, net Other Nonoperating, Gain (Loss) Other Nonoperating, Gain (Loss) Total Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Revenue Recognition, Policy Revenue Recognition, Policy [Policy Text Block] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block]