Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 332	$ 506	$ 14
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax rate	21.00%	21.00%	35.00%
Income tax expense (benefit) at federal statutory rate	$ 70	$ 106	$ 5
Dividends received deduction	(35)	(49)	(36)
Valuation allowance	0	9	(5)
Tax credit	(4)	0	5
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0	(71)
Other	1	(5)	1
Income tax expense (benefit)	$ 32	$ 61	$ (101)
Effective tax rate	9.60%	12.10%	(721.40%)

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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

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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 valuation allowance for deferred tax assets.

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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.

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