Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 569	$ 89	$ 134
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax rate	21.00%	35.00%	35.00%
Income tax expense (benefit) at federal statutory rate	$ 119	$ 31	$ 47
Dividends received deduction	(49)	(36)	(27)
Valuation allowance	9	(5)	(2)
Tax credit	0	5	2
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	(116)	0
Other	(5)	0	1
Income tax expense (benefit)	$ 74	$ (121)	$ 21
Effective tax rate	13.00%	(136.00%)	15.70%

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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