CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Class A Common Stock	Common Stock Common Stock	Common Stock Class A Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2020				29,600,000	1,996,000
Beginning balance at Dec. 31, 2020				$ 29,600	$ 1,996	$ (177,545)	$ 96,850	$ 304,626	$ (2,560)
Beginning balance (in shares) at Dec. 31, 2020						(13,384,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Class A Common Stock (in shares)				187,000
Conversion of Class A Common Stock				$ 187
Stock compensation transactions, net (in shares)				120,000
Stock compensation transactions, net				$ 120
Conversion to Common Stock (in shares)					(187,000)
Conversion to Common Stock					$ (187)
Directors' compensation plan (in shares)						25,000
Directors’ Compensation Plan						$ 346	523
Purchases (in shares)						(1,232,000)
Purchases						$ (41,809)
Shares issued under incentive plans, net							(3,014)
Stock-based compensation expense							8,213
Net income	$ 90,803							90,803
Cash dividends per share: Common Stock: 2023 – $2.18; 2022 - $2.09; and 2021 – $2.97 Class A Common Stock: 2023 - $2.05; 2022 - $1.96; and 2021– $2.79		$ (48,837)	$ (3,609)					(52,446)
Pension liabilities adjustment, net of taxes	267								267
Ending balance (in shares) at Dec. 31, 2021				29,907,000	1,809,000
Ending balance (in shares) at Dec. 31, 2021			(522,000)			(14,591,000)
Ending balance at Dec. 31, 2021	255,970			$ 29,907	$ 1,809	$ (219,008)	102,572	342,983	(2,293)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Class A Common Stock (in shares)				3,000
Conversion of Class A Common Stock				$ 3
Stock compensation transactions, net (in shares)				96,000
Stock compensation transactions, net				$ 96
Conversion to Common Stock (in shares)					(3,000)
Conversion to Common Stock					$ (3)
Directors' compensation plan (in shares)						16,000
Directors’ Compensation Plan						$ 250	707
Purchases (in shares)						(1,087,000)
Purchases						$ (29,998)
Shares issued under incentive plans, net							(1,768)
Stock-based compensation expense							7,195
Net income	89,358							89,358
Cash dividends per share: Common Stock: 2023 – $2.18; 2022 - $2.09; and 2021 – $2.97 Class A Common Stock: 2023 - $2.05; 2022 - $1.96; and 2021– $2.79		$ (31,432)	$ (2,516)					(33,948)
Pension liabilities adjustment, net of taxes	1,537								1,537
Ending balance (in shares) at Dec. 31, 2022				30,006,000	1,806,000
Ending balance (in shares) at Dec. 31, 2022		(15,140,000)	(522,000)			(15,662,000)
Ending balance at Dec. 31, 2022	289,399			$ 30,006	$ 1,806	$ (248,756)	108,706	398,393	(756)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Class A Common Stock (in shares)				2,000
Conversion of Class A Common Stock				$ 2
Stock compensation transactions, net (in shares)				212,000
Stock compensation transactions, net				$ 212
Conversion to Common Stock (in shares)					(2,000)
Conversion to Common Stock					$ (2)
Directors' compensation plan (in shares)						12,000
Directors’ Compensation Plan						$ 197	880
Purchases (in shares)						(227,000)
Purchases						$ (6,895)
Shares issued under incentive plans, net							(4,289)
Stock-based compensation expense							8,010
Net income	56,319							56,319
Cash dividends per share: Common Stock: 2023 – $2.18; 2022 - $2.09; and 2021 – $2.97 Class A Common Stock: 2023 - $2.05; 2022 - $1.96; and 2021– $2.79		$ (32,612)	$ (2,628)					(35,240)
Pension liabilities adjustment, net of taxes	(227)								(227)
Ending balance (in shares) at Dec. 31, 2023				30,220,000	1,804,000
Ending balance (in shares) at Dec. 31, 2023		(15,355,000)	(522,000)			(15,877,000)
Ending balance at Dec. 31, 2023	$ 308,366			$ 30,220	$ 1,804	$ (255,454)	$ 113,307	$ 419,472	$ (983)