Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate reconciliation (percent)	29.70%	34.50%	29.70%	34.50%
Effective income tax rate reconciliation, including discrete items (percent)	17.40%	400.00%	26.40%	5.00%
Discrete income tax charge (benefit)	$ 12	$ 41	$ 9	$ 39
Charge (benefit) from tax rate change	13	36	2	36
Other items charge (benefit)	$ 1	1	2	(2)
Income tax charge related to remeasurement as a result of the Separation Transaction			$ 13	6
Income tax charge (benefit) related to prior year items		$ 6		5
Tax charge (benefit) for stock compensation				$ 2

Discrete Income Tax Expense (Benefit)

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- Definition

Effective Income Tax Rate Reconciliation, Including Discrete Items, Percent

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Effective Income Tax Rate Reconciliation, Remeasurement Due To Separation Agreement, Amount

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 740
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120384911&loc=d3e23163-113944

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense (benefit).

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