CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Earnings Reinvested in the Business [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Beginning balance at Dec. 31, 2021	$ 5,396	$ 111,352	$ 1,630,713	$ (634,408)	$ (174,628)	$ 938,425
Beginning balance (in shares) at Dec. 31, 2021				12,107,549
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	0	0	37,071	$ 0	0	37,071
Other comprehensive income (loss)	0	0	0	0	(237)	(237)
Cash dividends paid	0	0	(17,211)	0	0	(17,211)
Share-based compensation	0	4,163	0	0	0	4,163
Non-vested stock issued upon vesting	0	(2,478)	0	$ 2,478	0	0
Non-vested stock issued upon vesting (in shares)				(47,298)
Benefit plans	0	560	0	$ 618	0	1,178
Benefit plans (in shares)				(11,786)
Other	0	(624)	15	$ (1,070)	0	(1,679)
Other (in shares)				20,403
Ending balance at Mar. 31, 2022	5,396	112,973	1,650,588	$ (632,382)	(174,865)	961,710
Ending balance (in shares) at Mar. 31, 2022				12,068,868
Beginning balance at Dec. 31, 2022	5,396	124,043	1,702,700	$ (631,853)	(200,688)	999,598
Beginning balance (in shares) at Dec. 31, 2022				12,058,773
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	0	0	33,651	$ 0	0	33,651
Other comprehensive income (loss)	0	0	0	0	16,301	16,301
Cash dividends paid	0	0	(17,255)	0	0	(17,255)
Share-based compensation	0	2,267	0	0	0	2,267
Non-vested stock issued upon vesting	0	(11,956)	0	$ 11,956	0	0
Non-vested stock issued upon vesting (in shares)				(228,181)
Benefit plans	0	375	0	$ 952	0	1,327
Benefit plans (in shares)				(18,172)
Other	0	(2,140)	0	$ (5,528)	0	(7,668)
Other (in shares)				105,524
Ending balance at Mar. 31, 2023	$ 5,396	$ 112,589	$ 1,719,096	$ (624,473)	$ (184,387)	$ 1,028,221
Ending balance (in shares) at Mar. 31, 2023				11,917,944