Stock-Based Compensation (Tables)

9 Months Ended

Sep. 28, 2019

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") -- are included in the results of operations as follows:

	Three Months Ended				Nine Months Ended
	September 28, 2019		September 29, 2018		September 28, 2019		September 29, 2018
Compensation expense, all share-based payment plans	$	655	$	785	$	2,184	$	2,578

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

The following table summarizes our SSARs as of September 28, 2019.

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, 2019	380,982		$	3.42
Granted	—		—
Forfeited	(3,197	)	3.43
Vested	(115,080	)	3.31
Unvested, September 28, 2019	262,705		$	3.47	1.7 years	$	631	$	5,937

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

The following table summarizes PRSUs and RSUs as of September 28, 2019.

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, 2019	247,838		$	15.68
Granted	40,988		20.45
Forfeited	(4,093	)	16.39
Vested	(60,474	)	13.55
Unvested, September 28, 2019	224,259		$	17.11	2.1 years	$	1,839	$	5,068
Employee PRSUs	192,837		$	16.80	2.3 years	$	1,474	$	4,358
Nonemployee Director RSUs	31,422		$	19.01	1.7 years	$	365	$	710

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 assumption.

	Nine Months Ended
	September 28, 2019		September 29, 2018
Volatility rate	9.9	%	10.1	%
Risk-free interest rate	2.3	%	2.7	%
Expected dividend yield	.7	%	.7	%
Expected life of awards (years)	8.8		9.2

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

The following table summarizes activity under the stock option plans for the nine months ended September 28, 2019.

Stock Options	Number of Options Outstanding		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
Outstanding, January 1, 2019	1,466,264		$	13.94
Granted	151,145		21.10
Exercised	(91,739	)	10.48
Forfeited	(20,160	)	17.67
Outstanding, September 28, 2019	1,505,510		$	14.82	5.7 years	$	11,713
Exercisable, September 28, 2019	1,015,025		$	13.08	4.5 years	$	9,667