Stock-Based Compensation (Tables)

12 Months Ended

Dec. 29, 2018

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

Share-based Compensation, Stock Options, Activity

The following table provides a reconciliation of outstanding stock options for the fiscal year ended December 29, 2018.

	Shares Under Option		Weighted Average Price		Weighted Average Remaining Contract Life (Years)	Aggregate Intrinsic Value (000’s)
Outstanding December 30, 2017	404,301		$	110.04
Granted	78,721		192.59
IXYS converted awards	499,027		92.52
Exercised	(296,914	)	87.85
Forfeited	(15,779	)	120.59
Outstanding December 29, 2018	669,356		116.29		5.4	$	36,494
Exercisable December 29, 2018	420,422		100.14		4.8	28,542

Schedule of Nonvested Restricted Stock Units Activity

The following table provides a reconciliation of non-vested restricted share and share unit awards for the fiscal year ended December 29, 2018.

	Shares		Weighted Average Grant-Date Fair Value
Nonvested December 30, 2017	199,693		$	130.40
Granted	77,430		194.39
Vested	(104,062	)	123.45
Forfeited	(12,267	)	144.84
Nonvested December 29, 2018	160,794		164.61

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The Company uses the Black-Scholes option valuation model to determine the fair value of awards granted. The weighted average fair value of and related assumptions for options granted are as follows:

	2018	2017	2016
Weighted average fair value of options granted	$45.19	$30.77	$26.06
Assumptions:
Risk-free interest rate	2.79%	1.79%	1.37%
Expected dividend yield	0.77%	0.86%	0.97%
Expected stock price volatility	25.0%	23.0%	26.0%
Expected life of options (years)	4.4	4.4	4.6