Stock-Based Employee Compensation (Tables)

3 Months Ended

Jul. 03, 2016

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

Compensation Expense

The following table summarizes stock-based compensation expense by line items appearing in the Company’s Condensed Consolidated Statements of Operations:

	Three Months Ended
(in thousands)	July 3, 2016		June 28, 2015
Cost of revenue	$	779	$	683
Research and development	4,308		3,632
Selling, general and administrative	5,428		3,552
Discontinued operations	—		(32		)
Total stock-based compensation expense	$	10,515	$	7,835

Stock Option Activity

The following is a summary of the Company's stock option activity and related weighted average exercise prices for each category:

	Three Months Ended July 3, 2016
(shares in thousands)	Shares		Price
Beginning stock options outstanding	2,594		$	10.47
Exercised (1)	(308	)	6.10
Canceled	(86	)	14.45
Ending stock options outstanding	2,200		$	10.92
Ending stock options exercisable	1,590		$	9.05

(1) Upon exercise, the Company issues new shares of common stock.

Nonvested Restricted Stock Units Activity

The following table summarizes the Company's restricted stock unit activity and related weighted-average exercise prices for each category for the three months ended July 3, 2016:

	Three Months Ended July 3, 2016
(shares in thousands)	Shares		Weighted-average grant date fair value per share
Beginning RSUs outstanding	3,693		$	16.09
Granted	1,571		20.28
Released	(1,014	)	13.24
Forfeited	(114	)	16.44
Ending RSUs outstanding	4,136		$	18.37

Nonvested Performance-based Units Activity

The following table summarizes the Company's performance stock unit activity and related weighted-average exercise prices for each category for the three months ended July 3, 2016:

	Three Months Ended July 3, 2016
(shares in thousands)	Shares		Weighted-average grant date fair value per share
Beginning PSUs outstanding	204		$	9.04
Granted	—		—
Released	(78	)	7.85
Forfeited	(126	)	7.74
Ending PSUs outstanding	—		$	—

Fair Value Assumptions

The following weighted average assumptions were used to calculate the fair value of the market-based equity award using a Monte Carlo simulation model:

	June 15, 2016			June 15, 2015			June 15, 2014
Estimated fair value	$	28.01		$	33.08		$	21.00
Expected volatility	46.90		%	41.22		%	34.60		%
Expected term (in years)	1.80			1.80			1.80
Risk-free interest rate	0.70		%	0.65		%	0.38		%
Dividend yield	—		%	—		%	—		%

Employee Stock Purchase Plan Activity

Activity under the Company's ESPP for the three months ended July 3, 2016 is summarized in the following table:

(in thousands, except per share amounts)
Number of shares issued	208
Average issuance price	$	16.96
Number of shares available at July 3, 2016	3,564