Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Items	Noncontrolling Interest
Beginning balance (in shares) at Jan. 03, 2015		14,624,159			3,760,019
Beginning balance at Jan. 03, 2015	$ 265,459	$ 146	$ 98,769	$ 270,249	$ (87,727)	$ (17,146)	$ 1,168
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	34,683			34,389			294
Dividends declared	(7,380)			(7,380)
Activity under stock plans (in shares)					(139,000)
Activity under stock plans	4,160		886		$ 3,274
Tax benefits related to employees' and directors' stock plans	881		881
Purchases of Company common stock (in shares)					229,760
Purchases of Company common stock	(9,906)				$ (9,906)
Other comprehensive items	(19,952)					(19,826)	(126)
Ending balance (in shares) at Jan. 02, 2016		14,624,159			3,850,779
Ending balance at Jan. 02, 2016	267,945	$ 146	100,536	297,258	$ (94,359)	(36,972)	1,336
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	32,469			32,077			392
Dividends declared	(8,285)			(8,285)
Activity under stock plans (in shares)					(164,247)
Activity under stock plans	4,893		869		$ 4,024
Other comprehensive items	(12,743)					(12,665)	(78)
Ending balance (in shares) at Dec. 31, 2016		14,624,159			3,686,532
Ending balance at Dec. 31, 2016	284,279	$ 146	101,405	321,050	$ (90,335)	(49,637)	1,650
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	31,583			31,092			491
Dividends declared	(9,249)			(9,249)
Dividend paid to noncontrolling interest	(882)						(882)
Activity under stock plans (in shares)					(72,694)
Activity under stock plans	3,597		1,816		$ 1,781
Other comprehensive items	23,176					22,922	254
Ending balance (in shares) at Dec. 30, 2017		14,624,159			3,613,838
Ending balance at Dec. 30, 2017	$ 332,504	$ 146	$ 103,221	$ 342,893	$ (88,554)	$ (26,715)	$ 1,513