Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 1,045	$ 591	$ 634
Other Comprehensive Income
Change in unrealized gains and losses on investments, net of tax of $317, $186 and $(220), respectively	598	345	(405)
Amortization of pension actuarial gains and losses and prior service cost, net of tax of $7, $6 and $(2), respectively	7	10	(4)
Change in life deferred acquisition costs, life policy reserves and other, net of tax of $1, $(4) and $4, respectively	(2)	(6)	9
Other comprehensive income (loss)	603	349	(400)
Comprehensive Income	$ 1,648	$ 940	$ 234