Stockholders' Equity (Schedule of Components of Other Comprehensive Income (Loss), Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Comprehensive Income (Loss) [Line Items]
Unrealized gain (loss) on marketable securities, gross amount	$ 0	$ 0	$ 1
Unrealized gain (loss) on marketable securities, income tax (provision) benefit	0	1	0
Unrealized gain (loss) on marketable securities, net amount	0	1	1
Foreign currency translation, gross amount	(193)	(188)	55
Foreign currency translation, income tax (provision) benefit	5	40	(35)
Foreign currency translation, net amount	(188)	(148)	20
Gain (loss) on cash flow hedges, gross amount	3	0	9
Gain (loss) on cash flow hedges, income tax (provision) benefit	(1)	40	(3)
Gain (loss) on cash flow hedges, net amount	2	40	6
Pension and postretirement benefits, gross amount	4	(84)	88
Pension and postretirement benefits, income tax (provision) benefit	(1)	30	(30)
Pension and postretirement benefits, net amount	3	(54)	58
Total other comprehensive income (loss), gross amount	(186)	(272)	153
Total other comprehensive income (loss), income tax (provision) benefit	3	111	(68)
Total other comprehensive income (loss), net of tax	$ (183)	$ (161)	$ 85