Share-Based Compensation - Cash-Settled Awards (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash-settled share based units (in shares)	4,746,711	1,878,220
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash-settled share based units (in shares)	1,751,649	1,878,220
Share-based compensation liability	$ 12	$ 3
Performance Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash-settled share based units (in shares)	2,995,062	0
Share-based compensation liability	$ 10
Performance Share Units (PSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential pay out, cash-settled award base on performance	0.00%
Performance Share Units (PSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential pay out, cash-settled award base on performance	200.00%
Cash-Settled Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs	$ 43
Unrecognized compensation costs, not yet recognized	2 years

Commitment made to pay deferred cash remuneration expressed as a percentage of the individual's base salary.

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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 equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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