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Sale of Business - Summary of Gain on the Sale Within Other Expense (Income) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Proceeds on disposal, net of transaction costs	$ 1,180
Net assets disposed	656
Gain included in other expense, net	524
Income taxes	77
Gain on divestiture, net of tax	$ 447

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- Definition

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- Definition

Disposal group not including discontinued operations gain on sale net of tax.

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- Definition

Disposal group not including discontinued operations net assets disposed.

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- Definition

Disposal group not including discontinued operations tax effect.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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