Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Mar. 31, 2012
Consolidated Balance Sheets
Accounts receivable, allowance (in dollars)	$ 1,007	$ 582
Property and equipment, accumulated depreciation (in dollars)	$ 27,317	$ 23,803
Undesignated preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Undesignated preferred stock, Authorized shares	5,000,000	5,000,000
Undesignated preferred stock, issued shares	0	0
Undesignated preferred stock, outstanding shares	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, Authorized shares	120,000,000	120,000,000
Common stock, issued shares	26,845,205	26,553,299
Common stock, outstanding shares	24,988,502	24,793,911
Treasury stock, common shares	1,856,703	1,759,388