Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Retained Earnings [Member] Common Class A [Member]	Retained Earnings [Member] Common Class B [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Common Stock Outstanding [Member] Common Class A [Member]	Common Stock Outstanding [Member] Common Class B [Member]	Treasury Stock, Common [Member]	Additional Paid-in Capital [Member]	Noncontrolling Interest [Member]	Common Class A [Member]	Common Class B [Member]	Total
Balance at Dec. 31, 2023			$ 307,510	$ (12,037)	$ 214	$ 1,065	$ (454)	$ 44,260	$ 0			$ 340,558
Balance (in shares) at Dec. 31, 2023					2,142	10,620
Net earnings			15,874							$ 2,545	$ 13,329	15,874
Cash dividends declared on common stock	$ (129)	$ (747)								(129)	(747)
Issuance of restricted common stock						$ 6		(6)
Issuance of restricted common stock (in shares)						58
Forfeiture of restricted common stock (in shares)						(6)
Foreign currency translation adjustment, net of taxes				(3,776)								(3,776)
Unrealized losses on interest rate swap cash flow hedge, net of taxes				340								340
Stock-based compensation expense								804				804
Change in unfunded SERP liability, net of taxes				15								15
Balance at Mar. 31, 2024			322,508	(15,457)	$ 213	$ 1,061	(6,737)	45,069	0			346,657
Balance (in shares) at Mar. 31, 2024					2,131	10,574
Forfeiture of restricted common stock						$ 0
Purchases of common stock				0	$ (1)	$ (10)	$ (6,283)					(6,283)
Purchases of common stock (in shares)					(11)	(98)
Purchases of common stock								11
Unrealized holding gains on marketable securities, net of taxes				1								1
Balance at Dec. 31, 2024			345,031	(17,227)	$ 212	$ 1,046		31,514	80,586			360,576
Balance (in shares) at Dec. 31, 2024					2,115	10,425
Redemption value adjustment attributable to noncontrolling interest			0						(390)
Net earnings			17,874						838	2,875	14,999	17,874
Cash dividends declared on common stock	$ (127)	$ (737)								$ (127)	$ (737)
Issuance of restricted common stock						$ 13		(13)				0
Issuance of restricted common stock (in shares)						129
Forfeiture of restricted common stock (in shares)						(2)
Foreign currency translation adjustment, net of taxes				(1,248)								(1,248)
Unrealized losses on interest rate swap cash flow hedge, net of taxes				(588)								(588)
Stock-based compensation expense								1,179				1,179
Change in unfunded SERP liability, net of taxes				(28)								(28)
Balance at Mar. 31, 2025			$ 362,041	$ (19,091)	$ 212	$ 1,059		$ 32,680	$ 81,034			376,901
Balance (in shares) at Mar. 31, 2025					2,115	10,552
Unrealized holding gains on marketable securities, net of taxes												$ 0