Income Taxes - Reconciliation Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits at January 1	$ 34,000,000	$ 0	$ 0
Gross increase in prior year positions	0	0	0
Gross decrease in prior year positions	0	0	0
Gross increase in current year positions	0	34,000,000	0
Settlements with tax authorities	0	0	0
Lapse of statute of limitations	0	0	0
Gross unrecognized tax benefits at December 31	$ 34,000,000	$ 34,000,000	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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