Share-based Compensation (Tables)

3 Months Ended

Mar. 30, 2018

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Share-Based Compensation Expense Recorded In Consolidated Net Income in the Consolidated Statements of Operations

The table below summarizes share-based compensation expense recorded in consolidated net income in the consolidated statements of operations (in thousands):

	ThreeMonths Ended
	March 30,		March 31,
	2018		2017
Selling, general and administrative	$	1,924	$	1,358
Research and development and engineering		84		43
Cost of revenue		36		68
Total share-based compensation expense	$	2,044	$	1,469

Fair Value of TSR Performance-Based Restricted Stock Units Estimated Using Monte-Carol Valuation Model

The fair value of the TSR-PSUs at the date of grant was estimated using the Monte-Carlo valuation model with the following assumptions:

	Three Months Ended March 30, 2018
Grant-date stock price	$	53.85
Expected volatility		30.35	%
Risk-free interest rate		2.37	%
Expected annual dividend yield		—
Fair value	$	70.49

2010 Incentive Award Plan

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Restricted Stock Issued and Outstanding

The table below summarizes activities relating to RSUs and DSUs issued and outstanding under the Company’s Amended and Restated 2010 Incentive Plan during the three months ended March 30, 2018:

	Shares (In thousands)			Weighted Average Grant Date Fair Value
Unvested at December 31, 2017		614		$	18.35
Granted		114		$	53.62
Vested		(166	)	$	18.50
Forfeited		—		$	—
Unvested at March 30, 2018		562		$	25.43
Expected to vest as of March 30, 2018		523

Performance-Based Awards Issued and Outstanding

The table below summarizes the activities relating to the performance-based awards issued and outstanding under the Company’s Amended and Restated 2010 Incentive Plan during the three months ended March 30, 2018:

	Shares (In thousands)		Weighted Average Grant Date Fair Value
Unvested at December 31, 2017		89	$	24.00
Granted		48	$	62.17
Vested		—	$	—
Forfeited		—	$	—
Unvested at March 30, 2018		137	$	37.28