Statement of Financial Position (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Current assets:
Accounts receivable allowance for doubtful accounts	$ 2,609	$ 2,656
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	37,973,275	37,921,213
Common stock, shares outstanding	31,046,566	30,885,354
Treasury stock, shares	6,926,709	7,035,859