CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 594	$ 403
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment	29	7
Net unrealized gains (losses) on securities	(262)	7
Net unrealized gains (losses) on derivatives	0	1
Defined benefit plans	0	5
Other	0	(1)
Total other comprehensive income (loss), net of tax	(233)	19
Total comprehensive income	$ 361	$ 422