Income Taxes - Temporary Differences (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal and state loss carryforwards	$ 2,147	$ 2,051
Investments	189	246
Insurance reserves	0	187
Compensation and benefits	269	295
Other assets	132	124
Total gross assets before valuation allowance	2,737	2,903
Less: Valuation allowance	388	638
Assets, net of valuation allowance	2,349	2,265
Net unrealized investment gains	(769)	(145)
Insurance reserves	(45)	0
Deferred policy acquisition costs	(66)	(493)
Other liabilities	(11)	(17)
Total gross liabilities	(891)	(655)
Net deferred income tax asset (liability)	$ 1,458	$ 1,610