Stock-Based Compensation (Stock-Based Awards Issued During The Period) (Details) (USD $)	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number granted	52,400	63,550
Grant date fair value	$ 59.72	$ 44.18
Performance Share Awards (PSAs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number granted	52,400	60,850
Grant date fair value	$ 53.56	$ 38.14