Stockholders' Equity 1 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Accumulated Other Comprehensive Loss
Foreign currency translation losses, net	$ (108)				$ (65)				$ (108)	$ (65)	$ (123)
Unrealized losses on cash flow hedges, net of tax	0				0				0	0	(3)
Total accumulated other comprehensive loss	(108)				(65)				(108)	(65)	(126)
Cash Dividends
Declaration Date	Jan. 23, 2012	Nov. 09, 2011	Aug. 03, 2011	May 12, 2011	Feb. 02, 2011	Dec. 02, 2010	Jul. 28, 2010	May 12, 2010
Dividend Per Share	$ 0.25	$ 0.05	$ 0.05	$ 0.05	$ 0.04	$ 0.04	$ 0.04	$ 0.04
Record Date	Feb. 14, 2012	Nov. 22, 2011	Aug. 16, 2011	May 23, 2011	Feb. 14, 2011	Dec. 13, 2010	Aug. 09, 2010	May 31, 2010
Total Amount	$ 117	$ 25	$ 25	$ 25	$ 21	$ 20	$ 20	$ 21	$ 192	$ 82	$ 83
Payment Date	Mar. 13, 2012	Dec. 14, 2011	Sep. 14, 2011	Jun. 16, 2011	Mar. 14, 2011	Dec. 22, 2010	Aug. 19, 2010	Jun. 16, 2010

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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