Accounting For Share-Based Compensation 2 (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Share Based Compensation Arrangement by Share Based Payment Award (Textual) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			600,000	1,200,000
Company's common stock purchase price as a percentage of the closing price of the stock on the last day of the plan period			95.00%
Stock purchase plan, maximum number of shares	30,000,000		30,000,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			700,000	600,000
Shares of Restricted Stock Awards and Restricted Stock Units Granted During Period	Less than 0.1 million	Less than 0.1 million
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 20.19	$ 21.69	$ 24.04	$ 21.30
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	100,000		3,700,000	4,700,000
Shares of Restricted Stock Awards and Restricted Stock Units Granted During Period		Less than 0.1 million
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 20.40	$ 22.19	$ 24.49	$ 21.39