Stock Based Compensation - Summary of Unrecognized Compensation Expense (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Stock Options
Additional Disclosures for equity-based plans
Unrecognized compensation expense of options, net of forfeitures	$ 0
Unrecognized compensation expense, expected to be recognized over a weighted-average period (in years)	0 years
RSUs
Additional Disclosures for equity-based plans
Unrecognized compensation expense of awards other than options, net of forfeitures	$ 51
Unrecognized compensation expense, expected to be recognized over a weighted-average period (in years)	2 years 3 months 7 days
RSAs
Additional Disclosures for equity-based plans
Unrecognized compensation expense of awards other than options, net of forfeitures	$ 2
Unrecognized compensation expense, expected to be recognized over a weighted-average period (in years)	14 days

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.

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 (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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