Stock-Based Compensation (Tables)

3 Months Ended

Mar. 27, 2016

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

Stock Option Activity Under The Principal Option Plans

Option activity under the principal option plans as of March 27, 2016 and changes during the three months ended March 27, 2016 were as follows:

	Number of Shares		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 27, 2015	2,265,992		$	16.59	4.49	$	19
Granted	16,200		6.04
Exercised	(35,943	)	7.80
Forfeited or expired	(153,481	)	20.67
Outstanding at March 27, 2016	2,092,768		$	16.36	4.11	$	1,053
Vested and expected to vest at March 27, 2016	2,040,374		$	16.50	3.99	$	984
Exercisable at March 27, 2016	1,744,174		$	17.38	3.17	$	623

Assumptions And Weighted-Average Fair Values Of Share-Based Payment Units Under Black-Scholes Option Pricing Model

The weighted-average fair values and assumptions were as follows:

Three months ended	March 27, 2016			March 29, 2015
Weighted-average fair value of grants	$	2.15		$	5.54
Valuation assumptions:
Expected life (in years)	3.97			5.53
Expected dividend yield	0.00		%	0.00		%
Expected volatility	44.19		%	46.05		%
Risk-free interest rate	1.435		%	1.540		%

Nonvested Service Based Restricted Stock Units

Nonvested restricted stock units as of March 27, 2016 and changes during the three months ended March 27, 2016 were as follows:

	Number of Shares		Weighted- Average Vest Date (in years)	Weighted- Average Grant Date Fair Value
Nonvested at December 27, 2015	942,916		0.74	$	16.88
Granted	505,680			$	7.25
Vested	(309,350	)		$	6.64
Forfeited	(34,224	)		$	13.15
Nonvested at March 27, 2016	1,105,022		1.51	$	15.46
Vested and expected to vest at March 27, 2016	990,689		1.43
Vested and deferred at March 27, 2016	345,625		—