CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 393	$ 335	$ 796	$ 699
Other comprehensive income, net of tax:
Foreign currency translation adjustment	23	(28)	30	(39)
Net unrealized gains on securities	57	217	64	410
Net unrealized gains on derivatives	0	1	1	2
Defined benefit plans	0	6	5	6
Other	0	0	(1)	0
Total other comprehensive income, net of tax	80	196	99	379
Total comprehensive income	$ 473	$ 531	$ 895	$ 1,078