Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock, Common [Member]	Total
Balance (in shares) at Dec. 31, 2020	7,025
Balance at Dec. 31, 2020	$ 7,441	$ 12,438	$ 367,627	$ 154	$ (13,312)	$ 374,348
Net earnings			25,654			25,654
Unrealized loss on available-for-sale securities, net of tax				(134)		(134)
Dividends paid March 13, $1.00 per share regular, $5.25 per share extra			(44,083)			(44,083)
Other (in shares)	17
Other		1,305	0		533	1,838
Unrealized loss on available-for-sale securities, net of tax				(134)		(134)
Balance (in shares) at Dec. 31, 2021	7,042
Balance at Dec. 31, 2021	$ 7,441	13,743	349,198	20	(12,779)	357,623
Net earnings			20,699			20,699
Unrealized loss on available-for-sale securities, net of tax				(123)		(123)
Dividends paid March 13, $1.00 per share regular, $5.25 per share extra			(31,826)			(31,826)
Other (in shares)	21
Other		1,056	0		623	1,679
Unrealized loss on available-for-sale securities, net of tax				(123)		$ (123)
Balance (in shares) at Dec. 31, 2022	7,063					7,062,872
Balance at Dec. 31, 2022	$ 7,441	14,799	338,071	(103)	(12,156)	$ 348,052
Net earnings			34,559			34,559
Unrealized loss on available-for-sale securities, net of tax				125		125
Dividends paid March 13, $1.00 per share regular, $5.25 per share extra			(28,385)			(28,385)
Other (in shares)	19
Other		1,232			673	1,905
Unrealized loss on available-for-sale securities, net of tax				125		$ 125
Balance (in shares) at Dec. 31, 2023	7,082					7,084,384
Balance at Dec. 31, 2023	$ 7,441	$ 16,031	$ 344,245	$ 22	$ (11,483)	$ 356,256