Stockholders' Equity 1 (Details) (USD $) In Millions, except Per Share data	3 Months Ended	6 Months Ended
Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Components of comprehensive income
Net income	$ 236		$ 222		$ 477	$ 439
Net unrealized gain on cash flow hedges, net of tax	0		1		0	2
Foreign currency translation adjustments	(85)		74		(68)	40
Total comprehensive income	151		297		409	481
Cash Dividends
Declaration Date	Aug. 03, 2011	May 12, 2011	Jul. 28, 2010	May 12, 2010
Dividend Per Share	$ 0.05	$ 0.05	$ 0.04	$ 0.04
Record Date	Aug. 16, 2011	May 23, 2011	Aug. 09, 2010	May 31, 2010
Total Amount	$ 25	$ 25	$ 20	$ 21
Payment Date	Sep. 14, 2011	Jun. 16, 2011	Aug. 19, 2010	Jun. 16, 2010

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

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