Employee Benefit Plans (Details) (USD $)	3 Months Ended
	Jun. 30, 2013 item
Employee Benefit Plans
Number of stock incentive plans	3
Stock options
Number of Shares
Options outstanding at the beginning of the period (in shares)	1,744,000
Exercised (in shares)	(19,000)
Expired (in shares)	(31,000)
Options outstanding at the end of the period (in shares)	1,694,000
Weighted Average Exercise Price Per Share
Options outstanding at the beginning of the period (in dollars per share)	$ 1.74
Exercised (in dollars per share)	$ 1.41
Expired (in dollars per share)	$ 2.28
Options outstanding at the end of the period (in dollars per share)	$ 1.74
Restricted Stock Units
Weighted Average Exercise Price Per Share
Number of shares of common stock receivable upon vesting of each RSU	1
Number of Shares
Restricted stock units outstanding at the beginning of the period (in shares)	210,000
Restricted stock units outstanding at the end of the period (in shares)	210,000
2007 Plan
Employee Benefit Plans
Shares of common stock available for grant	921,000