Income Taxes - Temporary Differences (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal and state loss carryforwards	$ 2,201	$ 1,030
Investments	337	1,440
Compensation and benefits	301	369
Other assets	86	330
Total gross assets before valuation allowance	2,925	3,169
Less: Valuation allowance	638	653
Assets, net of valuation allowance	2,287	2,516
Net unrealized investment gains	(236)	(824)
Insurance reserves	(214)	(342)
Deferred policy acquisition costs	(663)	(556)
Other liabilities	(17)	(13)
Total gross liabilities	(1,130)	(1,735)
Net deferred income tax asset (liability)	$ 1,157	$ 781

Amount of deferred tax liability attributable to taxable temporary differences.

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