Consolidated Condensed Statements of Equity - USD ($) $ in Thousands	Total	Total VPG, Inc. Stockholders' Equity	Common Stock	Class B Convertible Common Stock	Treasury Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Balance, beginning at Dec. 31, 2018	$ 218,453	$ 218,415	$ 1,307	$ 103	$ (8,765)	$ 196,666	$ 66,569	$ (37,465)	$ 38
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	8,326	8,243					8,243		83
Other comprehensive (loss) income	686	686						686
Share-based compensation expense	514	514				514
Restricted stock issuances	(598)	(598)	4			(602)
Distributions to noncontrolling interests	(34)								(34)
Balance, ending at Mar. 30, 2019	227,878	227,791	1,311	103	(8,765)	196,578	75,343	(36,779)	87
Balance, beginning at Dec. 31, 2019	241,752	241,360	1,312	103	(8,765)	197,125	89,288	(37,703)	392
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	3,292	3,312					3,312		(20)
Other comprehensive (loss) income	(5,500)	(5,500)						(5,500)
Share-based compensation expense	379	379				379
Restricted stock issuances	(791)	(791)	4			(795)
Distributions to noncontrolling interests	(25)								(25)
Balance, ending at Mar. 28, 2020	$ 239,107	$ 238,760	$ 1,316	$ 103	$ (8,765)	$ 196,709	$ 92,600	$ (43,203)	$ 347