$MRK
Merck & Co., Inc. Stock $mrk

$mrk Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000162828024006850 Filed on February 26, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$15.78B	$14.63B	$60.12B
YoY Change	8.89%	5.78%	1.4%
Cost Of Revenue	$2.961B	$3.340B	$13.90B
YoY Change	-11.66%	-0.62%	-8.25%
Gross Profit	$12.81B	$11.29B	$46.22B
YoY Change	15.08%	7.84%	4.72%
Gross Profit Margin	81.23%	77.17%	76.88%
Selling, General & Admin	$2.457B	$2.751B	$10.30B
YoY Change	-0.04%	4.68%	5.36%
% of Gross Profit	19.17%	24.37%	22.28%
Research & Development	$3.974B	$8.838B	$29.71B
YoY Change	-6.84%	191.2%	150.9%
% of Gross Profit	31.01%	78.28%	64.28%
Depreciation & Amortization	$511.0M	$964.0M	$1.800B
YoY Change	14.06%	8.07%	0.0%
% of Gross Profit	3.99%	8.54%	3.89%
Operating Expenses	$6.431B	$11.59B	$40.01B
YoY Change	-4.36%	104.64%	85.1%
Operating Profit	$6.383B	-$299.0M	$6.211B
YoY Change	44.71%	-106.22%	-72.42%
Interest Expense	$116.0M	$61.00M	$279.0M
YoY Change	-72.96%	-176.25%	-120.7%
% of Operating Profit	1.82%		4.49%
Other Income/Expense, Net	-$87.00M	-$174.0M	-$792.0M
YoY Change	-82.7%	-302.33%	120.0%
Pretax Income	$5.670B	-$2.046B	$1.889B
YoY Change	55.34%	-158.24%	-88.51%
Income Tax	$903.0M	-$821.0M	$1.512B
% Of Pretax Income	15.93%		80.04%
Net Earnings	$4.762B	-$1.226B	$365.0M
YoY Change	68.81%	-140.64%	-97.49%
Net Earnings / Revenue	30.19%	-8.38%	0.61%
Basic Earnings Per Share	$1.88		$0.14
Diluted Earnings Per Share	$1.87	-$0.48	$0.14
COMMON SHARES
Basic Shares Outstanding	2.533B shares	2.534B shares	2.537B shares
Diluted Shares Outstanding	2.544B shares		2.547B shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$5.619B	$7.093B	$7.093B
YoY Change	-45.9%	-46.23%	-46.23%
Cash & Equivalents	$5.579B	$6.841B	$6.841B
Short-Term Investments	$40.00M	$252.0M	$252.0M
Other Short-Term Assets	$7.950B	$8.368B	$7.645B
YoY Change	18.01%	16.72%	6.64%
Inventory	$6.510B	$6.358B	$6.358B
Prepaid Expenses
Receivables	$11.37B	$10.35B	$10.35B
Other Receivables	$744.0M	$723.0M	$723.0M
Total Short-Term Assets	$31.45B	$32.17B	$32.17B
YoY Change	-5.86%	-9.95%	-9.95%
LONG-TERM ASSETS
Property, Plant & Equipment	$23.05B	$23.05B	$24.49B
YoY Change	5.92%	7.6%	7.55%
Goodwill	$21.18B	$21.20B
YoY Change	-0.13%	-0.03%
Intangibles	$17.57B	$18.01B
YoY Change	-11.51%	-11.14%
Long-Term Investments	$1.527B	$1.501B	$1.501B
YoY Change	-31.59%	-18.73%	-18.73%
Other Assets	$12.33B	$12.00B	$9.310B
YoY Change	32.0%	37.95%	26.67%
Total Long-Term Assets	$74.40B	$74.51B	$74.51B
YoY Change	0.01%	1.46%	1.46%
TOTAL ASSETS
Total Short-Term Assets	$31.45B	$32.17B	$32.17B
Total Long-Term Assets	$74.40B	$74.51B	$74.51B
Total Assets	$105.8B	$106.7B	$106.7B
YoY Change	-1.81%	-2.28%	-2.28%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$3.514B	$3.922B	$3.922B
YoY Change	-4.51%	-8.02%	-8.02%
Accrued Expenses	$13.13B	$15.19B	$15.19B
YoY Change	0.97%	7.3%	7.3%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$3.077B	$1.300B	$1.372B
YoY Change	15.16%	-23.53%	-29.5%
Total Short-Term Liabilities	$25.10B	$25.69B	$25.69B
YoY Change	8.51%	6.0%	6.0%
LONG-TERM LIABILITIES
Long-Term Debt	$31.14B	$33.68B	$33.68B
YoY Change	10.93%	17.18%	17.18%
Other Long-Term Liabilities	$8.262B	$8.792B	$8.792B
YoY Change	0.22%	5.63%	5.63%
Total Long-Term Liabilities	$39.40B	$42.48B	$42.48B
YoY Change	8.5%	14.59%	14.59%
TOTAL LIABILITIES
Total Short-Term Liabilities	$25.10B	$25.69B	$25.69B
Total Long-Term Liabilities	$39.40B	$42.48B	$42.48B
Total Liabilities	$64.50B	$68.17B	$69.09B
YoY Change	8.5%	11.19%	9.38%
SHAREHOLDERS EQUITY
Retained Earnings	$56.70B	$53.90B
YoY Change	-8.61%	-11.76%
Common Stock	$46.39B	$46.30B
YoY Change	0.28%	0.28%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$40.36B	$37.58B	$37.58B
YoY Change
Total Liabilities & Shareholders Equity	$105.8B	$106.7B	$106.7B
YoY Change	-1.81%	-2.28%	-2.28%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$4.762B	-$1.226B	$365.0M
YoY Change	68.81%	-140.64%	-97.49%
Depreciation, Depletion And Amortization	$511.0M	$964.0M	$1.800B
YoY Change	14.06%	8.07%	0.0%
Cash From Operating Activities	$3.090B	$246.0M	$13.01B
YoY Change	130.77%	-94.45%	-31.89%
INVESTING ACTIVITIES
Capital Expenditures	$861.0M	$989.0M	$3.863B
YoY Change	-14.5%	-13.93%	-11.96%
Acquisitions	$746.0M		$0.00
YoY Change			-100.0%
Other Investing Activities	$14.00M	$1.042B	$36.00M
YoY Change	-137.84%	-273.96%	-212.5%
Cash From Investing Activities	-$1.376B	$53.00M	-$14.08B
YoY Change	-41.67%	-103.03%	183.93%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net	$751.0M		$1.755B
YoY Change	75000.0%		-22.03%
Cash From Financing Activities	-$2.814B	-2.245B	-4.810B
YoY Change	37.0%	44.47%	-47.25%
NET CHANGE
Cash From Operating Activities	$3.090B	246.0M	13.01B
Cash From Investing Activities	-$1.376B	53.00M	-14.08B
Cash From Financing Activities	-$2.814B	-2.245B	-4.810B
Net Change In Cash	-$1.238B	-1.946B	-$5.864B
YoY Change	-58.55%	-272.52%	-227.31%
FREE CASH FLOW
Cash From Operating Activities	$3.090B	$246.0M	$13.01B
Capital Expenditures	$861.0M	$989.0M	$3.863B
Free Cash Flow	$2.229B	-$743.0M	$9.143B
YoY Change	571.39%	-122.65%	-37.83%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2022	us-gaap	Restructuring Charges RestructuringCharges	337000000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-466000000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1501000000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1341000000	usd
CY2023	mrk	Costs Expenses And Other CostsExpensesAndOther	58226000000	usd
CY2022	mrk	Costs Expenses And Other CostsExpensesAndOther	42839000000	usd
CY2021	mrk	Costs Expenses And Other CostsExpensesAndOther	34825000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	16444000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	13879000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1521000000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	365000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	14519000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	13049000000	usd
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0000310158
CY2023	us-gaap	Collaborative Arrangement Transaction Statement Of Income Or Comprehensive Income Extensible Enumeration CollaborativeArrangementTransactionStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#Revenues
CY2023Q4	us-gaap	Hedged Liability Statement Of Financial Position Extensible Enumeration HedgedLiabilityStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#LongTermDebtNoncurrent
CY2021	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherNonoperatingIncomeExpense
CY2022	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherNonoperatingIncomeExpense
CY2023	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherNonoperatingIncomeExpense
CY2023	us-gaap	Impairment Of Intangible Asset Indefinite Lived Excluding Goodwill Statement Of Income Or Comprehensive Income Extensible Enumeration ImpairmentOfIntangibleAssetIndefiniteLivedExcludingGoodwillStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#ResearchAndDevelopmentExpense
CY2023	us-gaap	Impairment Of Intangible Asset Finite Lived Statement Of Income Or Comprehensive Income Extensible Enumeration ImpairmentOfIntangibleAssetFiniteLivedStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#ResearchAndDevelopmentExpense
CY2023	us-gaap	Impairment Of Intangible Asset Indefinite Lived Excluding Goodwill Statement Of Income Or Comprehensive Income Extensible Enumeration ImpairmentOfIntangibleAssetIndefiniteLivedExcludingGoodwillStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#ResearchAndDevelopmentExpense
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2022Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2023Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2023Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-12-31
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	1-6571
CY2023	dei	Entity Registrant Name EntityRegistrantName	Merck & Co., Inc.
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	126 East Lincoln Avenue
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	Rahway
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	07065
CY2023	dei	City Area Code CityAreaCode	908
CY2023	dei	Local Phone Number LocalPhoneNumber	740-4000
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	NJ
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	22-1918501
CY2023	dei	Security12b Title Security12bTitle	Common Stock ($0.50 par value)
CY2023	dei	Trading Symbol TradingSymbol	MRK
CY2023	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2023	dei	Entity Small Business EntitySmallBusiness	false
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
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CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1512000000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1918000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	377000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	14526000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	12358000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Attributable To Noncontrolling Entity IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity	12000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Attributable To Noncontrolling Entity IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity	7000000	usd
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CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	3577103522	shares
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CY2021	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	840000000	usd
CY2021	us-gaap	Stockholders Equity Note Spinoff Transaction StockholdersEquityNoteSpinoffTransaction	5091000000	usd
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CY2021	mrk	Research And Development Asset Acquired Other Than Through Business Combination Written Off Asset Acquisition Three ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOffAssetAcquisitionThree	0	usd
CY2023	mrk	Research And Development Asset Acquired Other Than Through Business Combination Written Off Asset Acquisition Two ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOffAssetAcquisitionTwo	1192000000	usd
CY2022	mrk	Research And Development Asset Acquired Other Than Through Business Combination Written Off Asset Acquisition Two ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOffAssetAcquisitionTwo	0	usd
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CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-5864000000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	4606000000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	14000000	usd
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CY2021Q4	us-gaap	Restricted Cash RestrictedCash	71000000	usd
CY2020Q4	us-gaap	Restricted Cash RestrictedCash	103000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	12773000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	8167000000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	8153000000	usd
CY2023Q4	us-gaap	Restricted Cash RestrictedCash	68000000	usd
CY2022Q4	us-gaap	Restricted Cash RestrictedCash	79000000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	71000000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	6909000000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	12773000000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	8167000000	usd
CY2023	us-gaap	Nature Of Operations NatureOfOperations	Nature of Operations<div style="margin-top:5pt;text-align:justify;text-indent:45pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Merck & Co., Inc. (Merck or the Company) is a global health care company that delivers innovative health solutions through its prescription medicines, including biologic therapies, vaccines and animal health products. The Company’s operations are principally managed on a product basis and include two operating segments, Pharmaceutical and Animal Health, both of which are reportable segments. </span></div><div style="margin-top:5pt;text-align:justify;text-indent:45pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The Pharmaceutical segment includes human health pharmaceutical and vaccine products. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Human health vaccine products consist of preventive pediatric, adolescent and adult vaccines. The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities. </span></div><div style="margin-top:5pt;text-align:justify;text-indent:45pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The Animal Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners. </span></div><div style="margin-top:9pt"><span style="color:#00857c;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Spin-Off of Organon & Co. </span></div><div style="margin-top:3pt;text-align:justify;text-indent:45pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">On June 2, 2021, Merck completed the spin-off of products from its women’s health, biosimilars and established brands businesses into a new, independent, publicly traded company named Organon & Co. (Organon) through a distribution of Organon’s publicly traded stock to Company shareholders. The established brands included in the transaction consisted of dermatology, non-opioid pain management, respiratory, select cardiovascular products, as well as the rest of Merck’s diversified brands franchise. The historical results of the businesses that were contributed to Organon in the spin-off have been reflected as discontinued operations in the Company’s consolidated financial statements through the date of the spin-off (see Note 5).</span></div>
CY2023	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	segment
CY2023	mrk	Sales Discounts SalesDiscounts	12500000000	usd
CY2022	mrk	Sales Discounts SalesDiscounts	12300000000	usd
CY2021	mrk	Sales Discounts SalesDiscounts	12300000000	usd
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CY2023Q4	mrk	Accrual For Rebates AccrualForRebates	2300000000	usd
CY2022Q4	mrk	Accrual For Chargebacks AccrualForChargebacks	178000000	usd
CY2022Q4	mrk	Accrual For Rebates AccrualForRebates	2700000000	usd
CY2023	mrk	Revenue Recognition Goods Goods Return Period Afterto Expiration Date RevenueRecognitionGoodsGoodsReturnPeriodAftertoExpirationDate	P12M
CY2023	us-gaap	Depreciation Depreciation	1800000000	usd
CY2022	us-gaap	Depreciation Depreciation	1800000000	usd
CY2021	us-gaap	Depreciation Depreciation	1600000000	usd
CY2023	us-gaap	Advertising Expense AdvertisingExpense	2300000000	usd
CY2022	us-gaap	Advertising Expense AdvertisingExpense	2200000000	usd
CY2021	us-gaap	Advertising Expense AdvertisingExpense	2000000000	usd
CY2023	us-gaap	Restructuring And Related Cost Incurred Cost RestructuringAndRelatedCostIncurredCost	933000000	usd
CY2023	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<span style="color:#00857c;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Reclassifications —</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%"> </span>Certain reclassifications have been made to prior year amounts to conform to the current year presentation.
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:9pt;text-align:justify;text-indent:45pt"><span style="color:#00857c;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Use of Estimates —</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%"> </span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The consolidated financial statements are prepared in conformity with accounting principles generally accepted in the U.S. (GAAP) and, accordingly, include certain amounts that are based on management’s best estimates and judgments. Estimates are used when accounting for amounts recorded in connection with acquisitions, including initial fair value determinations of assets and liabilities in a business combination (primarily IPR&D, other intangible assets and contingent consideration), as well as subsequent fair value measurements. Additionally, estimates are used in determining such items as provisions for sales discounts, rebates and returns, depreciable and amortizable lives, recoverability of inventories, including those produced in preparation for product launches, amounts recorded for contingencies, environmental liabilities, accruals for contingent sales-based milestone payments and other reserves, pension and other postretirement benefit plan assumptions, share-based compensation assumptions, restructuring costs, impairments of long-lived assets (including intangible assets and goodwill) and investments, and taxes on income. Because of the uncertainty inherent in such estimates, actual results may differ from these estimates.</span></div>
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CY2021	us-gaap	Disposal Group Including Discontinued Operation Other Expense DisposalGroupIncludingDiscontinuedOperationOtherExpense	556000000	usd
CY2021	us-gaap	Disposal Group Including Discontinued Operation Revenue DisposalGroupIncludingDiscontinuedOperationRevenue	2512000000	usd
CY2021	us-gaap	Disposal Group Including Discontinued Operation Costs Of Goods Sold DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold	789000000	usd
CY2021	us-gaap	Disposal Group Including Discontinued Operation General And Administrative Expense DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense	877000000	usd
CY2021	mrk	Disposal Group Including Discontinued Operations Research And Development Expenses DisposalGroupIncludingDiscontinuedOperationsResearchAndDevelopmentExpenses	103000000	usd
CY2021	mrk	Disposal Group Including Discontinued Operations Restructuring Costs DisposalGroupIncludingDiscontinuedOperationsRestructuringCosts	1000000	usd
CY2021	mrk	Disposal Group Including Discontinued Operation Other Income Expense Net DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpenseNet	15000000	usd
CY2021	us-gaap	Disposal Group Including Discontinued Operation Operating Expense DisposalGroupIncludingDiscontinuedOperationOperatingExpense	1755000000	usd
CY2021	us-gaap	Discontinued Operation Income Loss From Discontinued Operation During Phase Out Period Before Income Tax DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax	757000000	usd
CY2021	us-gaap	Discontinued Operation Tax Effect Of Income Loss From Discontinued Operation During Phase Out Period DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod	50000000	usd
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	707000000	usd
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CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	704000000	usd
CY2023Q4	us-gaap	Hedged Liability Fair Value Hedge HedgedLiabilityFairValueHedge	1056000000	usd
CY2022Q4	us-gaap	Hedged Liability Fair Value Hedge HedgedLiabilityFairValueHedge	0	usd
CY2023Q4	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	56000000	usd
CY2022Q4	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	0	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	342000000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	239000000	usd
CY2023Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	30551000000	usd
CY2022Q4	us-gaap	Derivative Assets DerivativeAssets	433000000	usd
CY2022Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	409000000	usd
CY2022Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	28681000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	342000000	usd
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CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	433000000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	409000000	usd
CY2023Q4	us-gaap	Derivative Asset Not Offset Policy Election Deduction DerivativeAssetNotOffsetPolicyElectionDeduction	215000000	usd
CY2023Q4	us-gaap	Derivative Liability Not Offset Policy Election Deduction DerivativeLiabilityNotOffsetPolicyElectionDeduction	215000000	usd
CY2022Q4	us-gaap	Derivative Asset Not Offset Policy Election Deduction DerivativeAssetNotOffsetPolicyElectionDeduction	220000000	usd
CY2022Q4	us-gaap	Derivative Liability Not Offset Policy Election Deduction DerivativeLiabilityNotOffsetPolicyElectionDeduction	220000000	usd
CY2023Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	3000000	usd
CY2023Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	0	usd
CY2022Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	66000000	usd
CY2022Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	19000000	usd
CY2023Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	124000000	usd
CY2023Q4	us-gaap	Derivative Liability After Offset Subject To Master Netting Arrangement DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement	24000000	usd
CY2022Q4	us-gaap	Derivative Asset After Offset Subject To Master Netting Arrangement DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement	147000000	usd
CY2022Q4	us-gaap	Derivative Liability After Offset Subject To Master Netting Arrangement DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement	170000000	usd
CY2023	us-gaap	Revenues Revenues	60115000000	usd
CY2022	us-gaap	Revenues Revenues	59283000000	usd
CY2021	us-gaap	Revenues Revenues	48704000000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-466000000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1501000000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1341000000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-393000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-339000000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1756000000	usd
CY2023Q4	us-gaap	Foreign Currency Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months ForeignCurrencyCashFlowHedgeGainLossToBeReclassifiedDuringNext12Months	-40000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	337000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	0	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	337000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	569000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	0	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	569000000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	764000000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1284000000	usd
CY2023Q4	mrk	Debt Securitiesand Equity Securities Fvni DebtSecuritiesandEquitySecuritiesFVNI	1101000000	usd
CY2022Q4	mrk	Debt Securitiesand Equity Securities Fvni DebtSecuritiesandEquitySecuritiesFVNI	1853000000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	411000000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-462000000	usd
CY2022Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	832000000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	832000000	usd
CY2023	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	10000000	usd
CY2023	us-gaap	Equity Securities Without Readily Determinable Fair Value Downward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueDownwardPriceAdjustmentAnnualAmount	61000000	usd
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CY2022	us-gaap	Equity Securities Without Readily Determinable Fair Value Downward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueDownwardPriceAdjustmentAnnualAmount	12000000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentCumulativeAmount	299000000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Downward Price Adjustment Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueDownwardPriceAdjustmentCumulativeAmount	80000000	usd
CY2022Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	456000000	usd
CY2021Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	777000000	usd
CY2023	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	15000000	usd
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CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	117000000	usd
CY2022	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	119000000	usd
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CY2022	mrk	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Other FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityOther	56000000	usd
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CY2022Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	456000000	usd
CY2023Q4	us-gaap	Business Combination Contingent Consideration Liability Current BusinessCombinationContingentConsiderationLiabilityCurrent	128000000	usd
CY2023Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	32000000000	usd
CY2023Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	35100000000	usd
CY2022Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	26700000000	usd
CY2022Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	30700000000	usd
CY2023	us-gaap	Accounts Receivable Sale AccountsReceivableSale	3000000000	usd
CY2022	us-gaap	Accounts Receivable Sale AccountsReceivableSale	2500000000	usd
CY2023Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	3000000	usd
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CY2022Q4	us-gaap	Derivative Collateral Right To Reclaim Securities DerivativeCollateralRightToReclaimSecurities	19000000	usd
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CY2022Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	1841000000	usd
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CY2022Q4	mrk	Inventory Work In Process And Raw Materials Excluding Supplies InventoryWorkInProcessAndRawMaterialsExcludingSupplies	7063000000	usd
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CY2022Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	238000000	usd
CY2023Q4	us-gaap	Inventory Gross InventoryGross	10268000000	usd
CY2022Q4	us-gaap	Inventory Gross InventoryGross	9142000000	usd
CY2023Q4	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	562000000	usd
CY2022Q4	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	293000000	usd
CY2023Q4	mrk	Inventory Net And Inventory Noncurrent InventoryNetAndInventoryNoncurrent	9706000000	usd
CY2022Q4	mrk	Inventory Net And Inventory Noncurrent InventoryNetAndInventoryNoncurrent	8849000000	usd
CY2023Q4	us-gaap	Inventory Net InventoryNet	6358000000	usd
CY2022Q4	us-gaap	Inventory Net InventoryNet	5911000000	usd
CY2023Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	3348000000	usd
CY2022Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	2938000000	usd
CY2022Q4	us-gaap	Lifo Inventory Amount LIFOInventoryAmount	3100000000	usd
CY2023Q4	us-gaap	Lifo Inventory Amount LIFOInventoryAmount	3100000000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	21264000000	usd
CY2022	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-60000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	21204000000	usd
CY2023	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-7000000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	21197000000	usd
CY2023Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	531000000	usd
CY2022Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	531000000	usd
CY2023Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	41603000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	23592000000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	18011000000	usd
CY2022Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	41746000000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	21477000000	usd
CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	20269000000	usd
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CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	1600000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	1400000000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	1100000000	usd
CY2023Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	1300000000	usd
CY2022Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	1700000000	usd
CY2023Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	33683000000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	28745000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	1400000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	2500000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	2200000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	1500000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	2100000000	usd
CY2023Q4	mrk	Long Term Debt Interest Payable Year One LongTermDebtInterestPayableYearOne	1200000000	usd
CY2023Q4	mrk	Long Term Debt Interest Payable Year Two LongTermDebtInterestPayableYearTwo	1100000000	usd
CY2023Q4	mrk	Long Term Debt Interest Payable Year Three LongTermDebtInterestPayableYearThree	1100000000	usd
CY2023Q4	mrk	Long Term Debt Interest Payable Year Four LongTermDebtInterestPayableYearFour	1000000000	usd
CY2023Q4	mrk	Long Term Debt Interest Payable Year Five LongTermDebtInterestPayableYearFive	1000000000	usd
CY2023Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	6000000000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	339000000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	334000000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	343000000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	347000000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	335000000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	340000000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	122000000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	57000000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	117000000	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.209
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y9M18D
CY2022	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y10M24D
CY2021	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y10M24D
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1437000000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1346000000	usd
CY2023Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	285000000	usd
CY2022Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	281000000	usd
CY2023Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	928000000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1013000000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	1213000000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	1294000000	usd
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y
CY2023Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.033
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.031
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	325000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	268000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	222000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	139000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	109000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	326000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	1389000000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	176000000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	1213000000	usd
CY2023Q4	mrk	Lessee Operating Lease Lease Notyet Commenced Amount LesseeOperatingLeaseLeaseNotyetCommencedAmount	188000000	usd
CY2023	mrk	Environmental Loss Contingency Statement Of Financial Position Extensible Enumeration Not Disclosed Flag EnvironmentalLossContingencyStatementOfFinancialPositionExtensibleEnumerationNotDisclosedFlag	liabilities
CY2023Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	42000000	usd
CY2022Q4	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	39000000	usd
CY2023	mrk	Term For Paying Off Environmental Liabilities TermForPayingOffEnvironmentalLiabilities	P15Y
CY2023	us-gaap	Environmental Exit Costs Reasonably Possible Additional Loss EnvironmentalExitCostsReasonablyPossibleAdditionalLoss	40000000	usd
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	6500000000	shares
CY2023Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	81000000	shares
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	645000000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	541000000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	498000000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	479000000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	96000000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	78000000	usd
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	69000000	usd
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	117.89
CY2022	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	87.10
CY2021	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	75.99
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	21.69
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	15.45
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	9.80
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.031
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.031
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.031
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.034
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.030
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.010
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.224
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.225
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	13719000	shares
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	70.55
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	1826000	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	117.89
CY2023	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1934000	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	64.57
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	84000	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	111.37
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	13527000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	77.54
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y2M12D
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	442000000	usd
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	13119000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice	76.63
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P6Y1M6D
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	438000000	usd
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	9451000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	68.97
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P5Y2M12D
CY2023Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	379000000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	95000000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	225000000	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	106000000	usd
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	30000000	usd
CY2022	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	30000000	usd
CY2021	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	27000000	usd
CY2023	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	125000000	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	384000000	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	202000000	usd
CY2022	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	175000000	usd
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	158000000	usd
CY2023Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	990000000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y10M24D
CY2023	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	199000000	usd
CY2023	us-gaap	Investment Income Interest InvestmentIncomeInterest	365000000	usd
CY2022	us-gaap	Investment Income Interest InvestmentIncomeInterest	157000000	usd
CY2021	us-gaap	Investment Income Interest InvestmentIncomeInterest	36000000	usd
CY2023	us-gaap	Interest Expense InterestExpense	1146000000	usd
CY2022	us-gaap	Interest Expense InterestExpense	962000000	usd
CY2021	us-gaap	Interest Expense InterestExpense	806000000	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-370000000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-237000000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-297000000	usd
CY2023	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	340000000	usd
CY2022	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-1419000000	usd
CY2021	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	1940000000	usd
CY2023	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-498000000	usd
CY2022	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-279000000	usd
CY2021	us-gaap	Net Periodic Defined Benefits Expense Reversal Of Expense Excluding Service Cost Component NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent	-212000000	usd
CY2023	mrk	Other Nonoperating Income Expense Other OtherNonoperatingIncomeExpenseOther	-153000000	usd
CY2022	mrk	Other Nonoperating Income Expense Other OtherNonoperatingIncomeExpenseOther	681000000	usd
CY2021	mrk	Other Nonoperating Income Expense Other OtherNonoperatingIncomeExpenseOther	256000000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-466000000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1501000000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1341000000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	1100000000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	937000000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	779000000	usd
CY2023	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	397000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	3453000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	2915000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2023	mrk	Income Tax Rate Reconciliation Asset Acquisition Three Amount IncomeTaxRateReconciliationAssetAcquisitionThreeAmount	2139000000	usd
CY2023	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Three Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionThreePercent	1.133
CY2022	mrk	Income Tax Rate Reconciliation Asset Acquisition Three Amount IncomeTaxRateReconciliationAssetAcquisitionThreeAmount	0	usd
CY2022	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Three Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionThreePercent	0
CY2021	mrk	Income Tax Rate Reconciliation Asset Acquisition Three Amount IncomeTaxRateReconciliationAssetAcquisitionThreeAmount	0	usd
CY2021	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Three Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionThreePercent	0
CY2023	mrk	Income Tax Rate Reconciliation Asset Acquisition Two Amount IncomeTaxRateReconciliationAssetAcquisitionTwoAmount	253000000	usd
CY2023	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Two Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionTwoPercent	0.134
CY2022	mrk	Income Tax Rate Reconciliation Asset Acquisition Two Amount IncomeTaxRateReconciliationAssetAcquisitionTwoAmount	0	usd
CY2022	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Two Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionTwoPercent	0
CY2021	mrk	Income Tax Rate Reconciliation Asset Acquisition Two Amount IncomeTaxRateReconciliationAssetAcquisitionTwoAmount	0	usd
CY2021	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Two Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionTwoPercent	0
CY2023	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	70000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.037
CY2022	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	108000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.007
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	102000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.007
CY2023	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Amount EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationAmount	42000000	usd
CY2023	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Percent EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationPercent	0.022
CY2022	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Amount EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationAmount	-3000000	usd
CY2022	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Percent EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationPercent	0
CY2021	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Amount EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationAmount	8000000	usd
CY2021	mrk	Effective Income Tax Rate Reconciliation Acquisition Related Costs And Amortization Percent EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCostsAndAmortizationPercent	0.001
CY2023	us-gaap	Income Tax Reconciliation Nondeductible Expense Restructuring Charges IncomeTaxReconciliationNondeductibleExpenseRestructuringCharges	41000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	0.022
CY2022	us-gaap	Income Tax Reconciliation Nondeductible Expense Restructuring Charges IncomeTaxReconciliationNondeductibleExpenseRestructuringCharges	11000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	0.001
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Restructuring Charges IncomeTaxReconciliationNondeductibleExpenseRestructuringCharges	61000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	0.004
CY2023	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-941000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.498
CY2022	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-1821000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.111
CY2021	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-1456000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.105
CY2023	mrk	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income Foreign Derived Intangible Income Deduction Amount EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeForeignDerivedIntangibleIncomeDeductionAmount	-80000000	usd
CY2023	mrk	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income Foreign Derived Intangible Income Deduction Percent EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeForeignDerivedIntangibleIncomeDeductionPercent	-0.043
CY2022	mrk	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income Foreign Derived Intangible Income Deduction Amount EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeForeignDerivedIntangibleIncomeDeductionAmount	462000000	usd
CY2022	mrk	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income Foreign Derived Intangible Income Deduction Percent EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeForeignDerivedIntangibleIncomeDeductionPercent	0.028
CY2021	mrk	Effective Income Tax Rate Reconciliation Global Intangible Low Taxed Income Foreign Derived Intangible Income Deduction Amount EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomeForeignDerivedIntangibleIncomeDeductionAmount	-75000000	usd
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CY2023	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.113
CY2022	us-gaap	Income Tax Reconciliation Tax Credits Research IncomeTaxReconciliationTaxCreditsResearch	117000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.007
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.008
CY2023	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-117000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.062
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-110000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.007
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0
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CY2023	mrk	Effective Income Tax Rate Reconciliation Deduction Inventory Donations Percent EffectiveIncomeTaxRateReconciliationDeductionInventoryDonationsPercent	0.035
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CY2022	mrk	Effective Income Tax Rate Reconciliation Deduction Inventory Donations Percent EffectiveIncomeTaxRateReconciliationDeductionInventoryDonationsPercent	0.003
CY2021	mrk	Effective Income Tax Rate Reconciliation Deduction Inventory Donations Amount EffectiveIncomeTaxRateReconciliationDeductionInventoryDonationsAmount	41000000	usd
CY2021	mrk	Effective Income Tax Rate Reconciliation Deduction Inventory Donations Percent EffectiveIncomeTaxRateReconciliationDeductionInventoryDonationsPercent	0.003
CY2023	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	0	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	0
CY2022	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	-10000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	-0.001
CY2021	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	-275000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	-0.020
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CY2023	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Four Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionFourPercent	0
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CY2022	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Four Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionFourPercent	0
CY2021	mrk	Income Tax Rate Reconciliation Asset Acquisition Four Amount IncomeTaxRateReconciliationAssetAcquisitionFourAmount	356000000	usd
CY2021	mrk	Effective Income Tax Rate Reconciliation Asset Acquisition Four Percent EffectiveIncomeTaxRateReconciliationAssetAcquisitionFourPercent	0.026
CY2023	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-13000000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.007
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-3000000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-107000000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-129000000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	24000000	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1899000000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1568000000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	37000000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.003
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1512000000	usd
CY2023	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.800
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1918000000	usd
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.117
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1521000000	usd
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.110
CY2023Q4	us-gaap	Tax Cuts And Jobs Act Of2017 Transition Tax For Accumulated Foreign Earnings Liability TaxCutsAndJobsActOf2017TransitionTaxForAccumulatedForeignEarningsLiability	1500000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-15622000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1011000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1854000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	17511000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	15433000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	12025000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1889000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	16444000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	13879000000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	928000000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	2265000000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	74000000	usd
CY2023	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	2435000000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1164000000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1273000000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	48000000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	57000000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-13000000	usd
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	3411000000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	3486000000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1334000000	usd
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CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1510000000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	240000000	usd
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CY2022	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	71000000	usd
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CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	187000000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1512000000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1918000000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1521000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Goodwill And Intangible Assets DeferredTaxAssetsGoodwillAndIntangibleAssets	0	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	1308000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Goodwill And Intangible Assets DeferredTaxAssetsGoodwillAndIntangibleAssets	0	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	2575000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets In Process Research And Development DeferredTaxAssetsInProcessResearchAndDevelopment	2099000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets In Process Research And Development DeferredTaxAssetsInProcessResearchAndDevelopment	1341000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	86000000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Inventory Costs DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts	370000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	43000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Inventory Costs DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts	423000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	0	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	626000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Property Plant And Equipment DeferredTaxAssetsPropertyPlantAndEquipment	0	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	666000000	usd
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CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	335000000	usd
CY2023Q4	mrk	Deferred Tax Assets Unrecognized Tax Benefits DeferredTaxAssetsUnrecognizedTaxBenefits	147000000	usd
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CY2022Q4	mrk	Deferred Tax Assets Operating Loss Carryforwards And Other Tax Credit Carryforwards DeferredTaxAssetsOperatingLossCarryforwardsAndOtherTaxCreditCarryforwards	912000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	713000000	usd
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CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	520000000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	267000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	4593000000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2840000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	3614000000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	4307000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	656000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	599000000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	3937000000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2840000000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	3015000000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	4307000000	usd
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CY2022Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	1292000000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	871000000	usd
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CY2023Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	292000000	usd
CY2023Q4	mrk	Deferredtaxassetscreditlosscarryforwardsand No Lcarryforwardsdomestic DeferredtaxassetscreditlosscarryforwardsandNOLcarryforwardsdomestic	575000000	usd
CY2023	us-gaap	Income Taxes Paid IncomeTaxesPaid	4338000000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	3239000000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	2412000000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	12000000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	45000000	usd
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	21000000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1835000000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1529000000	usd
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1537000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	553000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	344000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	306000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	91000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	48000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	63000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	20000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	40000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	230000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	23000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	6000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	46000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	52000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	40000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	58000000	usd
CY2023	mrk	Unrecognized Tax Benefits Decrease Resulting From Spinoff Transaction UnrecognizedTaxBenefitsDecreaseResultingFromSpinoffTransaction	0	usd
CY2022	mrk	Unrecognized Tax Benefits Decrease Resulting From Spinoff Transaction UnrecognizedTaxBenefitsDecreaseResultingFromSpinoffTransaction	0	usd
CY2021	mrk	Unrecognized Tax Benefits Decrease Resulting From Spinoff Transaction UnrecognizedTaxBenefitsDecreaseResultingFromSpinoffTransaction	43000000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2384000000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1835000000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1529000000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2400000000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	2300000000	usd
CY2023Q4	us-gaap	Decrease In Unrecognized Tax Benefits Is Reasonably Possible DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible	25000000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	131000000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	54000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	-37000000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	388000000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	256000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	365000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	14519000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	12345000000	usd
CY2023	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	usd
CY2022	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	usd
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	704000000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	365000000	usd
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CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	14519000000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	14519000000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	13049000000	usd
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CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2537000000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2532000000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2530000000	shares
CY2023	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	10000000	shares
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	10000000	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	8000000	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	2547000000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	2542000000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	2538000000	shares
CY2023	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.14
CY2022	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	5.73
CY2021	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	4.88
CY2023	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
CY2022	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0
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CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.14
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.73
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.16
CY2023	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.14
CY2022	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	5.71
CY2021	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	4.86
CY2023	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2022	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.28
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.14
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.71
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.14
CY2023	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	5000000	shares
CY2022	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2000000	shares
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	9000000	shares
CY2023	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	segment
CY2023	us-gaap	Revenues Revenues	60115000000	usd
CY2022	us-gaap	Revenues Revenues	59283000000	usd
CY2021	us-gaap	Revenues Revenues	48704000000	usd
CY2023	mrk	Increase Decrease In Hedge Revenue IncreaseDecreaseInHedgeRevenue	244000000	usd
CY2022	mrk	Increase Decrease In Hedge Revenue IncreaseDecreaseInHedgeRevenue	810000000	usd
CY2021	mrk	Increase Decrease In Hedge Revenue IncreaseDecreaseInHedgeRevenue	-203000000	usd
CY2023	us-gaap	Proceeds From Sale Of Intangible Assets ProceedsFromSaleOfIntangibleAssets	118000000	usd
CY2022	us-gaap	Proceeds From Sale Of Intangible Assets ProceedsFromSaleOfIntangibleAssets	165000000	usd
CY2021	us-gaap	Proceeds From Sale Of Intangible Assets ProceedsFromSaleOfIntangibleAssets	218000000	usd
CY2023	us-gaap	Revenues Revenues	60115000000	usd
CY2022	us-gaap	Revenues Revenues	59283000000	usd
CY2021	us-gaap	Revenues Revenues	48704000000	usd
CY2023	us-gaap	Restructuring Charges RestructuringCharges	599000000	usd
CY2022	us-gaap	Restructuring Charges RestructuringCharges	337000000	usd
CY2021	us-gaap	Restructuring Charges RestructuringCharges	661000000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1889000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	16444000000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	13879000000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	23051000000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	21422000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	19279000000	usd
CY2023	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2023	dei	Auditor Location AuditorLocation	Florham Park, New Jersey
CY2023Q4	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2023Q4	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2023	dei	Auditor Firm AuditorFirmId	238

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$MRK
Merck & Co., Inc. Stock $mrk

2024 Q1 Form 10-K Financial Statement

#000162828024006850 Filed on February 26, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MRK Merck & Co., Inc. Stock $mrk

2024 Q1 Form 10-K Financial Statement

#000162828024006850 Filed on February 26, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MRK
Merck & Co., Inc. Stock $mrk