Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Mar. 31, 2013
Accounts receivable, allowance for doubtful accounts	$ 147	$ 971
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	49,826,807	49,007,491
Common stock, shares outstanding	41,326,074	41,466,921
Treasury stock, shares	8,500,733	7,540,570