Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Class A [Member] Retained Earnings [Member]	Common Class A [Member] Common Stock Outstanding [Member]	Common Class A [Member]	Common Class B [Member] Retained Earnings [Member]	Common Class B [Member] Common Stock Outstanding [Member]	Common Class B [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock, Common [Member]	Additional Paid-in Capital [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 31, 2021		$ 214			$ 1,038		$ 187,935	$ (18,863)	$ 0	$ 38,419	$ 0	$ 208,743
Balance (in shares) at Dec. 31, 2021		2,145			10,377
Net earnings							52,689					52,689
Cash dividends declared on common stock	$ (514)		$ (514)	$ (2,922)		$ (2,922)
Issuance of restricted common stock					$ 33					(33)
Issuance of restricted common stock (in shares)					323
Forfeiture of restricted common stock					$ (4)
Forfeiture of restricted common stock (in shares)					(40)
Forfeiture of restricted common stock, APIC										4
Repurchase of treasury stock (in shares)		(3)			(17)
Repurchase of treasury stock									(349)			(349)
Foreign currency translation adjustment, net of taxes								(8,196)				(8,196)
Unrealized gains on interest rate swap cashflow hedge, net of taxes								5,655				5,655
Unrealized holding losses on marketable securities, net of taxes								(11)				(11)
Stock-based compensation expense										2,382		2,382
Change in unfunded SERP liability, net of taxes								4,869				4,869
Balance at Dec. 31, 2022		$ 214			$ 1,067		237,188	(16,546)	(349)	40,772		262,346
Balance (in shares) at Dec. 31, 2022		2,142			10,643
Net earnings							73,831					73,831
Cash dividends declared on common stock	(512)		(512)	(2,997)		(2,997)
Issuance of restricted common stock					$ 1					(1)
Issuance of restricted common stock (in shares)					10
Forfeiture of restricted common stock					$ (3)
Forfeiture of restricted common stock (in shares)					(31)
Forfeiture of restricted common stock, APIC										3
Repurchase of treasury stock (in shares)					(2)
Repurchase of treasury stock									(105)			(105)
Foreign currency translation adjustment, net of taxes								6,684				6,684
Unrealized gains on interest rate swap cashflow hedge, net of taxes								(1,579)				(1,579)
Unrealized holding losses on marketable securities, net of taxes								1				1
Stock-based compensation expense										3,486		3,486
Change in unfunded SERP liability, net of taxes								(597)				(597)
Balance at Dec. 31, 2023		$ 214			$ 1,065		307,510	(12,037)	(454)	44,260		340,558
Balance (in shares) at Dec. 31, 2023		2,142			10,620
Net earnings							40,960				484	40,960
Cash dividends declared on common stock	$ (508)		$ (508)	$ (2,931)		$ (2,931)
Issuance of restricted common stock					$ 6					(6)
Issuance of restricted common stock (in shares)					58
Forfeiture of restricted common stock					$ (1)
Forfeiture of restricted common stock (in shares)					(17)
Forfeiture of restricted common stock, APIC										1
Repurchase of treasury stock (in shares)		(27)			(236)
Repurchase of treasury stock		$ (2)			$ (24)				(16,053)			(16,053)
Foreign currency translation adjustment, net of taxes								(5,543)				(5,543)
Unrealized gains on interest rate swap cashflow hedge, net of taxes								(1,231)				(1,231)
Unrealized holding losses on marketable securities, net of taxes								2				2
Stock-based compensation expense										3,740		3,740
Change in unfunded SERP liability, net of taxes								1,582				1,582
Acquisition resulting in redeemable noncontrolling interests ("NCI")		0			0		0	0	0	0	72,354	0
Redemption value adjustment on redeemable NCI							0				7,748	0
Purchase of common stock, APIC										26
Cancellation of treasury shares									16,507	(16,507)
Balance at Dec. 31, 2024		$ 212			$ 1,046		$ 345,031	$ (17,227)	$ 0	$ 31,514	$ 80,586	$ 360,576
Balance (in shares) at Dec. 31, 2024		2,115			10,425