Accounting for Share-Based Compensation 6 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Performance Share Units [Member] Grant Date [Member]	Sep. 30, 2013 Performance Share Units [Member] First Anniversary [Member]	Sep. 30, 2013 Performance Share Units [Member] Second Anniversary [Member]	Jun. 30, 2013 Employee Stock Purchase Plan [Member]	Sep. 30, 2013 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
1-year PSU awards vesting percentage			34.00%	33.00%	33.00%
Percentage of stock closing price on last day of offer period that ESPP participants can purchase Company stock						95.00%
Number of shares issued under Employee Stock Purchase Plan						0.1
Average price of shares issued under Employee Stock Purchase Plan						$ 27.19
Number of shares available for future issuances under Employee Stock Purchase Plan							29.7
Accounting for Share-Based Compensation (Textual) [Abstract]
Stock options issued	1.6	0.7
Computation of expected life, Simplified method	The Company’s computation of expected life was determined based on the simplified method (the average of the vesting period and option term).