Common Shares and Share-Based Compensation (Tables)

3 Months Ended

Apr. 03, 2020

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

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

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

	Three Months Ended
	April 3,		March 29,
	2020		2019
Selling, general and administrative	$	2,798	$	2,531
Research and development and engineering		193		111
Cost of revenue		208		85
Total share-based compensation expense	$	3,199	$	2,727

Schedule of Share ​Based ​Payment ​Award ​Performance ​Stock ​Awards ​Valuation ​Assumptions

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 April 3, 2020
Grant-date stock price	$	96.28
Expected volatility		34.25	%
Risk-free interest rate		1.35	%
Expected annual dividend yield		—
Fair value	$	126.65

Amended and Restated 2010 Incentive Plan

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

Restricted Stock Units and Deferred Stock Units 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 April 3, 2020:

	Shares (In thousands)			Weighted Average Grant Date Fair Value
Unvested at December 31, 2019		453		$	39.74
Granted		96		$	95.58
Vested		(94	)	$	51.42
Forfeited		—		$	—
Unvested at April 3, 2020		455		$	49.39
Expected to vest as of April 3, 2020		425

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 April 3, 2020:

	Shares (In thousands)			Weighted Average Grant Date Fair Value
Unvested at December 31, 2019		152		$	57.09
Granted		50		$	111.47
Performance adjustment (1)		60		$	28.80
Vested		(120	)	$	28.80
Unvested at April 3, 2020		142		$	89.05
Expected to vest as of April 3, 2020		173

(1) The amount shown represents performance adjustment for performance-based awards granted on February 28, 2017. These units vested at 200% during the three months ended April 3, 2020 based on the achievement of cumulative Non-GAAP EPS and applicable relative TSR performance conditions during the performance period of fiscal years 2017 through 2019.