Stockholders' Equity (Accumulated Other Comprehensive Income) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Currency Translation Adjustments, Balance	$ 193
Net Unrealized Gains (Losses) on Cash Flow Hedges, Balance	0
Net Unrealized Gains on Available- For-Sale Securities, Balance	2
Currency Translation Adjustments, Balance	(85)
Accumulated Other Comprehensive Income, Balance	110
Currency Translation Adjustments, Current period change	(23)	37
Net Unrealized Gains (Losses) on Cash Flow Hedges, Current period change	0	7
Net unrealized gains on available-for-sale securities, net of tax
Accumulated Other Comprehensive Income, Current period change	(23)	44
Currency Translation Adjustments, Balance	170
Net Unrealized Gains (Losses) on Cash Flow Hedges, Balance	0
Net Unrealized Gains on Available- For-Sale Securities, Balance	2
Currency Translation Adjustments, Balance	(85)
Accumulated Other Comprehensive Income, Balance	$ 87