Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Class A [Member] Retained Earnings [Member]	Common Class A [Member] AOCI Attributable to Parent [Member]	Common Class A [Member] Common Stock, Common Class A [Member]	Common Class A [Member] Common Stock, Common Class B [Member]	Common Class A [Member] Treasury Stock, Common [Member]	Common Class A [Member] Additional Paid-in Capital [Member]	Common Class A [Member]	Common Class B [Member] Retained Earnings [Member]	Common Class B [Member] AOCI Attributable to Parent [Member]	Common Class B [Member] Common Stock, Common Class A [Member]	Common Class B [Member] Common Stock, Common Class B [Member]	Common Class B [Member] Treasury Stock, Common [Member]	Common Class B [Member] Additional Paid-in Capital [Member]	Common Class B [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Common Stock, Common Class A [Member]	Common Stock, Common Class B [Member]	Treasury Stock, Common [Member]	Additional Paid-in Capital [Member]	Total
Balance at Dec. 31, 2021															$ 187,935	$ (18,863)	$ 214	$ 1,038	$ 38,419		$ 208,743
Net earnings							$ 821							$ 4,243	5,064	0	0	0	0		5,064
Cash dividends declared on common stock	$ (129)	$ 0	$ 0	$ 0	$ 0		(129)	$ (727)	$ 0	$ 0	$ 0	$ 0		(727)
Forfeiture of restricted common stock															0	0	0	(1)			0
Forfeiture of restricted common stock, APIC																			1
Foreign currency translation adjustment, net of taxes															0	(1,216)	0	0	0		(1,216)
Unrealized losses on interest rate swap cash flow hedge, net of taxes of $0															0	2,984	0	0	0		2,984
Unrealized holding gains on marketable securities, net of taxes																					0
Stock-based compensation expense															0	0	0	0	576		576
Change in unfunded SERP liability, net of taxes															0	61	0	0	0		61
Balance at Mar. 31, 2022															192,143	(17,034)	214	1,037	38,996		215,356
Balance at Dec. 31, 2022															237,188	(16,546)	214	1,067	(349)	$ 40,772	262,346
Net earnings							2,331							12,241	14,572	0	0	0	0	0	14,572
Cash dividends declared on common stock	$ (128)	$ 0	$ 0	$ 0	$ 0	$ 0	$ (128)	$ (747)	$ 0	$ 0	$ 0	$ 0	$ 0	$ (747)
Forfeiture of restricted common stock															0	0	0	(1)			0
Forfeiture of restricted common stock, APIC																			0	1
Foreign currency translation adjustment, net of taxes															0	1,998	0	0	0	0	1,998
Unrealized losses on interest rate swap cash flow hedge, net of taxes of $0															0	(894)	0	0	0	0	(894)
Unrealized holding gains on marketable securities, net of taxes															0	1	0	0	0	0	1
Stock-based compensation expense															0	0	0	0	0	902	902
Change in unfunded SERP liability, net of taxes															0	13	0	0	0	0	13
Balance at Mar. 31, 2023															$ 250,885	$ (15,428)	$ 214	$ 1,066	$ (349)	$ 41,675	$ 278,063