Stock-Based Compensation (Details 2) (Stock options, USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Stock options
Stock based compensation disclosure
Options outstanding, beginning of period (in shares)	5,361	5,624
Granted (in shares)	1,215	966
Exercised (in shares)	(405)	(1)
Canceled/forfeited (in shares)	(881)	(578)
Options outstanding, end of period (in shares)	5,290	6,011
Options outstanding (in dollars per share), beginning of period	$ 53.13	$ 57.78
Granted (in dollars per share)	$ 33.64	$ 23.72
Exercised (in dollars per share)	$ 29.64	$ 23.72
Canceled/forfeited (in dollars per share)	$ 99.98	$ 56.37
Options outstanding (in dollars per share), end of period	$ 42.65	$ 52.44
Options exercisable (in shares)	2,839	3,586
Weighted-average exercise price per share of exercisable options (in dollars per share)	$ 52.91	$ 68.60
Weighted-average remaining contractual life of exercisable options (in years)	3 years 73 days	3 years 36 days
Unamortized Compensation Cost related to Unvested Options	$ 23,765	$ 22,912
Unvested Options, Shares	2,451	2,425
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	1 year 256 days	1 year 292 days