Stock-Based Compensation (Tables)

6 Months Ended

Sep. 30, 2013

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

Schedule of Weighted-Average Assumptions Used to Estimate the Fair Value of Stock Options

The fair value of the options and employee stock purchase rights granted is estimated as of the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:

	ESPP
	Three months ended September 30,
	2013			2012
Expected life (years)	0.5			0.5
Risk-free interest rate	0.1		%	0.2		%
Volatility	57		%	50		%
Dividend yield	—		%	—		%
Weighted average fair value	$	3.67		$	1.50

The Company did not grant options during the three months ended September 30, 2013 and 2012.

	Six Months Ended September 30,
	Employee Stock Options						ESPP
	2013			2012			2013			2012
Expected life (years)	4.4			4.5			0.5			0.5
Risk-free interest rate	0.6		%	0.7		%	0.1		%	0.2		%
Volatility	49		%	54		%	57		%	50		%
Dividend yield	—		%	—		%	—		%	—		%
Weighted average fair value	$	2.95		$	2.47		$	3.67		$	1.50

Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units

The following table summarizes stock-based compensation expense related to stock options and RSUs (in thousands):

	Three Months Ended					Six Months Ended
	September 30,					September 30,
	2013			2012		2013			2012
Stock-based compensation expense by type of award
Stock options	$	737		$	601	$	1,339		$	2,089
Restricted stock units	3,099			7,031		6,223			13,151
Total stock-based compensation	3,836			7,632		7,562			15,240
Stock-based compensation (capitalized to) expensed from inventory	(2		)	2		(14		)	83
Total stock-based compensation expense	$	3,834		$	7,634	$	7,548		$	15,323

Summary of Stock-Based Compensation Expense

The following table summarizes stock-based compensation expense as it relates to the Company’s Condensed Consolidated Statement of Operations (in thousands):

	Three Months Ended					Six Months Ended
	September 30,					September 30,
	2013			2012		2013			2012
Stock-based compensation expense by cost centers
Cost of revenues	$	127		$	175	$	235		$	355
Research and development	1,524			3,714		3,322			7,919
Selling, general and administrative	2,185			3,743		4,005			6,966
Total stock-based compensation	$	3,836		$	7,632	$	7,562		$	15,240
Stock-based compensation (capitalized to) expensed from inventory	(2		)	2		(14		)	83
Total stock-based compensation expense	$	3,834		$	7,634	$	7,548		$	15,323