Stock Option Plans (Tables)

12 Months Ended

Mar. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Activity of Stock Options

Activity of stock options under our 2004 Plan, non-plan option awards and Omnibus Incentive Plan is set forth below:

	Number of Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (in Years)	Aggregate Intrinsic Value
						(in thousands)
Balance at March 31, 2013	1,203,990		$	13.26
Granted	66,690		41.80
Forfeited	(169,936	)	25.78
Exercised	(186,919	)	10.48
Balance at March 31, 2014	913,825		$	13.58
Vested and expected to vest—March 31, 2014	779,907		$	11.09	3.9	$	22,692
Exercisable—March 31, 2014	674,565		$	8.87	3.2	$	21,128

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range

The following table summarizes information about stock options outstanding at March 31, 2014:

	Options Outstanding
		Weighted-Average
		Remaining
	Stock Options	Contractual Life	Options
Exercise Price	Outstanding	(Years)	Exercisable
$4.93—$6.62	376,963	1.8	376,963
$7.30—$8.88	192,809	3.5	192,809
$16.94—$19.00	244,406	7.8	96,793
$30.01—$35.00	40,000	8.8	8,000
$35.01—$40.00	22,867	9.1	—
$40.01—$45.00	36,780	9.3	—
	913,825	4.6	674,565

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

	Fiscal Year Ended March 31,
	2014	2013	2012
Expected term (in years)	5.2 - 6.0	5.2	5.2 - 6.9
Expected volatility	38.2% - 39.7%	39.8% - 40.8%	41.0% - 42.0%
Risk-free interest rate	0.7% - 2.1%	0.8% - 1.1%	1.1% - 3.1%
Expected dividend rate	0%	0%	0%

Summary of Activity of Unvested Restricted Stock Units and Performance Share Units

The following table summarizes the activity of unvested restricted stock units and performance share units:

Shares-Based Awards	Shares		Weighted-Average Grant Date Fair Value
Unvested at March 31, 2013	71,165		$	21.73
Granted	65,352		41.36
Vested	(11,017	)	30.19
Forfeited	(36,590	)	29.67
Unvested at March 31, 2014	88,910		$	31.84