Condensed Consolidated Statements Of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2011		Dec. 31, 2010
Condensed Consolidated Statements Of Operations [Abstract]
Revenues	$ 30,839		$ 28,247		$ 91,035		$ 83,231
Cost of Sales	29,273		26,786		86,313		79,012
Gross Profit	1,566		1,461		4,722		4,219
Operating Expenses	1,047		965		3,135		2,808
Litigation Charges	27		189		145		213
Total Operating Expenses	1,074		1,154		3,280		3,021
Operating Income	492		307		1,442		1,198
Other Income (Expense), Net	(2)		7		12		19
Interest Expense	(64)		(53)		(192)		(140)
Income from Continuing Operations Before Income Taxes	426		261		1,262		1,077
Income Tax Expense	(126)		(106)		(380)		(369)
Income from Continuing Operations	300		155		882		708
Discontinued Operation - gain on sale, net of tax							72
Net Income	$ 300		$ 155		$ 882		$ 780
Diluted
Continuing operations	$ 1.20	[1]	$ 0.60	[1]	$ 3.51	[1]	$ 2.69	[1]
Discontinued operation - gain on sale							$ 0.27	[1]
Total	$ 1.20	[1]	$ 0.60	[1]	$ 3.51	[1]	$ 2.96	[1]
Basic
Continuing operations	$ 1.22	[1]	$ 0.61	[1]	$ 3.57	[1]	$ 2.73	[1]
Discontinued operation - gain on sale							$ 0.28	[1]
Total	$ 1.22	[1]	$ 0.61	[1]	$ 3.57	[1]	$ 3.01	[1]
Dividends Declared Per Common Share	$ 0.20		$ 0.18		$ 0.60		$ 0.54
Weighted Average Common Shares
Diluted	251		258		252		264
Basic	246		254		247		259

[1] Certain computations may reflect rounding adjustments.