XML 58 R47.htm IDEA: XBRL DOCUMENT
v3.24.1.u1

Restructuring - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs | $ 246 |
Restructuring Program, 2024 |  |
Restructuring Cost and Reserve [Line Items] |  |
Expected restructuring and related cost | $ 4,000 |
Estimate of cumulative pre tax costs that will be noncash | 60.00% |
Total pretax restructuring costs | $ 246 |
Cumulative costs since program inception | $ 436 |
Restructuring Program, 2019 |  |
Restructuring Cost and Reserve [Line Items] |  |
Total pretax restructuring costs |  | $ 97

X
- Definition Estimate of cumulative pre tax costs that will be noncash. + References No definition available. + Details
Name: | mrk_EstimateOfCumulativePreTaxCostsThatWillBeNoncash
Namespace Prefix: | mrk_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of costs incurred to date for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
Name: | us-gaap_RestructuringAndRelatedCostCostIncurredToDate1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
Name: | us-gaap_RestructuringAndRelatedCostExpectedCost1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
Name: | us-gaap_RestructuringAndRelatedCostIncurredCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
Name: | us-gaap_RestructuringCostAndReserveLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RestructuringPlanAxis=mrk_RestructuringProgram2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringPlanAxis=mrk_RestructuringProgram2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |