Condensed Consolidated Statement of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Items	Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU | ASU No. 2016-02	$ (17)			$ (17)
Beginning balance (in shares) at Dec. 29, 2018		14,624,159			3,514,163
Beginning balance at Dec. 29, 2018	374,571	$ 146	$ 104,731	393,578	$ (86,111)	$ (39,376)	$ 1,603
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	11,065			10,900			165
Dividend declared – Common Stock	(2,570)			(2,570)
Activity under stock plans	(372)		(1,951)		$ 1,579
Activity under stock plans (in shares)					(64,435)
Other comprehensive items	(681)					(648)	(33)
Ending balance (in shares) at Mar. 30, 2019		14,624,159			3,449,728
Ending balance at Mar. 30, 2019	381,996	$ 146	102,780	401,891	$ (84,532)	(40,024)	1,735
Beginning balance (in shares) at Dec. 28, 2019		14,624,159			3,214,888
Beginning balance at Dec. 28, 2019	427,079	$ 146	106,698	435,249	$ (78,778)	(37,620)	1,384
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	12,656			12,531			125
Dividend declared – Common Stock	(2,753)			(2,753)
Activity under stock plans	235		(1,241)		$ 1,476
Activity under stock plans (in shares)					(60,244)
Other comprehensive items	(12,945)					(12,934)	(11)
Ending balance (in shares) at Mar. 28, 2020		14,624,159			3,154,644
Ending balance at Mar. 28, 2020	$ 424,272	$ 146	$ 105,457	$ 445,027	$ (77,302)	$ (50,554)	$ 1,498