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Contingencies and Environmental Liabilities - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2014 legalmatter	Dec. 31, 2020 USD ($) legalmatter	Dec. 31, 2018 USD ($)
Patent litigation
Loss Contingencies [Line Items]
Litigation settlement, gain (loss) | $			$ 115
Loss contingency, claims settled, number		9
Commercial Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims number		2
Loss contingency, number of plaintiffs		2
Fosamax
Loss Contingencies [Line Items]
Loss contingency, pending claims number		3,520
Fosamax | Federal Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		970
Loss contingency, claims dismissed number	650
Loss contingency, claims on appeal, number		515
Fosamax | New Jersey State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		2,270
Fosamax | California State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		275
Fosamax | Other State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		4
Januvia
Loss Contingencies [Line Items]
Loss contingency, pending claims number		1,480
Januvia | Cases Company Agreed To Toll Statute Of Limitations
Loss Contingencies [Line Items]
Loss contingency, pending claims number		50
Januvia | Other State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		6
Vioxx
Loss Contingencies [Line Items]
Litigation settlement, gain (loss) | $		$ (25)

X

- Definition

Loss Contingency, Claims on Appeal, Number

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

+ Details

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- 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.

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- Definition

Number of claims dismissed.

+ References

No definition available.

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- Definition

Number of claims settled.

+ References

No definition available.

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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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- 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=121557415&loc=d3e14435-108349

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