Income Taxes 6 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Income Taxes (Textual) [Abstract]
Total deferred tax assets, net of valuation allowances	$ 750	$ 748
Net Operating loss carryforwards	876	891
Net operating loss carryforwards subject to expiration	722
Net operating loss carryforwards not subject to expiration	154
Net operating loss carryforwards expiration period	between 2013 and 2032
Decreased valuation allowance	(17)	(12)
Unremitted earnings	1,999	1,719
Liability for income taxes associated with uncertain tax positions	641	620
Liability for uncertain tax positions current	0	26
Deferred tax portion related to uncertain tax positions	56	43
Amount of interest and penalties accrued	118	98	82
Amount of interest and penalties recognized	20	16	12
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 410	$ 400
Deferred Tax Liability Not Recognized, Determination of Deferred Tax Liability is Not Practicable	It is not practicable to determine the amount of tax associated with such unremitted earnings.