XML 101 R77.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Contingencies and Environmental Liabilities - Fosamax Product Liability Litigation - Narrative (Details) - Fosamax - legalmatter | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2014 | Dec. 31, 2018 | Jul. 31, 2015 | Nov. 30, 2013
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, pending claims number |  | 3,900 |  |
Federal Court |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, pending claims number |  | 9 |  |
Loss contingency, claims dismissed number | 650 | 1,055 |  |
Loss contingency, claims on appeal, number |  | 515 |  |
New Jersey State Court |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, pending claims number |  | 2,555 |  |
Initial number of cases selected for review |  | 30 |  |
Subsequent number of cases selected for review | 50 |  | 25 | 50
California State Court |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, pending claims number |  | 275 |  |
Initial number of cases selected for review | 10 |  |  |
Other State Court |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Loss contingency, pending claims number |  | 4 |  |

X
- Definition Initial number of cases selected for review. + References No definition available. + Details
Name: | mrk_InitialNumberOfCasesSelectedForReview
Namespace Prefix: | mrk_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loss Contingency, Claims on Appeal, Number + References No definition available. + Details
Name: | mrk_LossContingencyClaimsonAppealNumber
Namespace Prefix: | mrk_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Subsequent number of cases selected for review. + References No definition available. + Details
Name: | mrk_SubsequentNumberOfCasesSelectedForReview
Namespace Prefix: | mrk_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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 No definition available. + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of claims dismissed. + References No definition available. + Details
Name: | us-gaap_LossContingencyClaimsDismissedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | srt_ProductOrServiceAxis=mrk_FosamaxMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=mrk_FederalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=mrk_NewJerseyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=mrk_CaliforniaStateCourtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=mrk_OtherStateCourtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |