Stock-Based Compensation and Employee Stock Purchase Plan (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Stock-based employee compensation expense	$ 765,000	$ 418,000	$ 1,827,000	$ 1,013,000
Stock-Based Awards
Unamortized stock-based compensation expense related to unvested stock awards	7,400,000		7,400,000
Weighted average period of recognition for unrecognized compensation costs (in years)			3.14
Employee Stock Purchase Plan
Unamortized stock-based compensation expense related to unvested stock awards	84,000		84,000
Weighted average period of recognition for unrecognized compensation costs (in years)			0.5
Stock-based employee compensation expense	115,000	117,000	356,000	312,000
Annual maximum total purchases price amount per employee	$ 25,000		$ 25,000