Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings [Member]	Accumulated Other Comprehensive Income	Noncontrolling Interest	Treasury Stock, Common
Balance at beginning of period at Dec. 31, 2021	$ 1,909,449	$ 166,822	$ 979,096	$ 727,021	$ 40,214	$ 4	$ (3,708)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	226,846	0	0	219,513	7,279	54	0
Dividends, Common Stock	(39,964)	0	0	39,964	0	0	0
Stock option exercises	272	7	265	0	0	0	0
Restricted stock awards, net of forfeitures	0	147	(147)	0	0	0	0
Employee share-based compensation earned	3,687	0	3,687	0	0	0	0
Purchase of Company common stock	(256,355)	0	(24,613)	(227,638)	0	0	(4,104)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	162	0	0	0	0	162	0
Other	1,127	0	1,127	0	0	0	0
Balance at end of period at Mar. 31, 2022	1,842,646	166,976	957,161	678,932	47,493	(104)	(7,812)
Balance at beginning of period at Dec. 31, 2022	1,673,423	156,089	958,329	544,384	16,538	232	(2,149)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Comprehensive income	145,127	0	0	144,763	299	65	0
Dividends, Common Stock	$ (41,207)	0	0	(41,207)	0	0	0
Dividends declared per share	$ 270
Stock option exercises	$ 8,763	298	8,465	0	0	0	0
Restricted stock awards, net of forfeitures	0	132	(133)	0	0	0	1
Employee share-based compensation earned	4,478	0	4,478	0	0	0	0
Purchase of Company common stock	(167,305)	0	(16,500)	(148,373)	0	0	(2,432)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	107	0	0	0	0	107	0
Other	1,271	0	1,271	0	0	0	0
Balance at end of period at Mar. 31, 2023	$ 1,621,901	$ 156,519	$ 953,368	$ 499,567	$ 16,837	$ 190	$ (4,580)