Stock-Based Compensation (Tables)

3 Months Ended

Mar. 28, 2020

Share-based Payment Arrangement [Abstract]

Schedule of stock-based compensation expense under all share-based payment plans [Table Text Block]

Stock-based compensation expense under all share-based payment plans -- our Employee Stock Purchase Plan, stock option plans, stock-settled stock appreciation rights ("SSARs") and restricted stock units ("RSUs") -- was included in the results of operations as follows:

	Three Months Ended
	March 28, 2020		March 30, 2019
Compensation expense, all share-based payment plans	$	745	$	753

Schedule of share-based compensation, stock-settled stock appreciation rights award activity [Table Text Block]

The following table summarizes our SSARs as of March 28, 2020.

Stock-Settled Stock Appreciation Rights	Number of Rights		Weighted- Average Award Date Value		Weighted- Average Remaining Contractual Life	Unrecognized Compensation Cost		Aggregate Intrinsic Value
Unvested, January 1, 2020	262,705		$	3.47
Granted	—		—
Forfeited	(2,254	)	3.53
Vested	(113,757	)	3.31
Unvested, March 28, 2020	146,694		$	3.59	1.6 years	$	462	$	3,550

Schedule of share-based compensation, restricted stock units award activity [Table Text Block]

The following table summarizes PRSUs and RSUs as of March 28, 2020.

Restricted Stock Units	Number of Stock Units		Weighted- Average Grant Date Value		Weighted- Average Remaining Contractual Life	Unrecognized Compensation Cost		Aggregate Intrinsic Value
Unvested, January 1, 2020	224,259		$	17.11
Granted	86,959		23.72
Forfeited	(1,871	)	17.37
Vested	(49,518	)	14.54
Unvested, March 28, 2020	259,829		$	19.81	3.0 years	$	3,444	$	6,288
Employee PRSUs	228,407		$	19.92	3.5 years	$	3,176	$	5,528
Nonemployee Director RSUs	31,422		$	19.01	1.1 years	$	268	$	760

Schedule of share-based payment award, stock options, valuation assumptions [Table Text Block]

The fair values of stock-based awards granted were estimated at the dates of grant with the following weighted-average assumptions.

	Three Months Ended
	March 28, 2020		March 30, 2019
Volatility rate	9.7	%	9.9	%
Risk-free interest rate	.6	%	2.5	%
Expected dividend yield	.4	%	.7	%
Expected life of awards (years)	6.2		7.4

Schedule of share-based compensation, stock options activity [Table Text Block]

The following table summarizes activity under the stock option plans for the three months ended March 28, 2020.

Stock Options	Number of Options Outstanding		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
Outstanding, January 1, 2020	1,428,082		$	15.13
Granted	28,397		24.20
Exercised	—		—
Forfeited	(7,335	)	15.34
Outstanding, March 28, 2020	1,449,144		$	15.30	5.5 years	$	12,897
Exercisable, March 28, 2020	936,457		$	13.43	4.3 years	$	10,082