Income Taxes (Components Of Deferred Tax Balances) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Income Tax Disclosure [Abstract]
Receivable allowances	$ 84	$ 44
Deferred revenue	106	114
Compensation and benefit related accruals	553	447
AWP litigation accrual	17	175
Loss and credit carryforwards	341	400
Other	264	256
Subtotal	1,365	1,436
Less: valuation allowance	(118)	(101)
Total assets	1,247	1,335
Inventory valuation and other assets	(2,089)	(1,635)
Fixed assets and systems development costs	(267)	(263)
Intangibles	(734)	(544)
Other	(24)	(53)
Total liabilities	(3,114)	(2,495)
Net deferred tax liability	(1,867)	(1,160)
Current net deferred tax asset	16	0
Current net deferred tax liability	(1,626)	(1,092)
Long-term deferred tax asset	21	20
Long-term deferred tax liability	$ (278)	$ (88)