Stock-Based Compensation (Schedule Of Restricted Stock Rights Activity, Excluding Performance-Based Activity) (Details) (Restricted Stock Rights [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Restricted Stock Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance	15,918
Granted	5,980
Vested	(4,424)
Forfeited or cancelled	(637)
Ending balance	16,837
Weighted-average grant date fair value, beginning balance	$ 16.85
Weighted-average grant date fair values of restricted stock rights granted	$ 22.31	$ 12.53
Weighted-average grant date fair value, vested during period	$ 17.46
Weighted-average grant date fair value, forfeited or cancelled during period	$ 16.90
Weighted-average grant date fair value, ending balance	$ 18.63