Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 441	$ 202	$ 1,252	$ 466
Other comprehensive (loss) income, net of tax (Note 10)
Unrealized gain (loss) on cash flow hedges, net of income tax (expense) benefit of $(2), $2, $(1) and $10	1	(3)	19	(14)
Defined benefit plans, net of income tax	0	0	0	(1)
Foreign currency translation adjustment, net of income tax benefit (expense) of $0, $(21), $1 and $(30)	(35)	120	(221)	318
Other comprehensive (loss) income, net of tax	(34)	117	(202)	303
Comprehensive income	$ 407	$ 319	$ 1,050	$ 769