CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 1,877	$ 2,171	$ 2,850
Changes in:
Unrealized net capital gains and losses	433	(1,306)	280
Unrealized foreign currency translation adjustments	10	(58)	(40)
Unrecognized pension and other postretirement benefit cost	(104)	48	(725)
Other comprehensive income (loss), after-tax	339	(1,316)	(485)
Comprehensive income	$ 2,216	$ 855	$ 2,365