CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Treasury Stock, Common	Accumulated Other Comprehensive Income (Loss), Net	Total Shareholders' Equity	Noncontrolling Interests
Balance at Dec. 31, 2020	$ 930,670	$ 436,538	$ 514,176	$ (82,240)	$ 18,371	$ 886,845	$ 43,825
Increase (Decrease) in Stockholders' Equity
Net income	118,557		118,534			118,534	23
Other comprehensive income (loss)	(28,232)				(28,232)	(28,232)
Issuance of 82,840, 72,593, and 63,527 common shares under stock based compensation awards for 2023, 2022 and 2021, respectively	2,714		1,547	1,167		2,714
Cost of 310,522, 149,819, and 713,132 shares of common stock acquired for treasury for 2023, 2022, and 2021, respectively	(33,136)			(33,136)		(33,136)
Common stock dividend ($1.30, $1.26, and $1.21 per share for 2023, 2022, and 2021, respectively)	(30,470)		(30,470)			(30,470)
Contributions from noncontrolling interests	10,358					0	10,358
Distributions to noncontrolling interests	(997)					0	(997)
Balance at Dec. 31, 2021	$ 969,464	436,538	603,787	(114,209)	(9,861)	916,255	53,209
Increase (Decrease) in Stockholders' Equity
Issuance of common shares per stock based compensation awards, shares	63,527
Common stock acquired for treasury, shares	713,132
Common stock dividend (in dollars per share)	$ 1.21
Net income	$ 120,532		120,509			120,509	23
Other comprehensive income (loss)	(137,829)				(137,829)	(137,829)
Issuance of 82,840, 72,593, and 63,527 common shares under stock based compensation awards for 2023, 2022 and 2021, respectively	3,165		1,762	1,403		3,165
Cost of 310,522, 149,819, and 713,132 shares of common stock acquired for treasury for 2023, 2022, and 2021, respectively	(6,836)			(6,836)		(6,836)
Common stock dividend ($1.30, $1.26, and $1.21 per share for 2023, 2022, and 2021, respectively)	(31,196)		(31,196)			(31,196)
Contributions from noncontrolling interests	7,700					0	7,700
Distributions to noncontrolling interests	(1,234)					0	(1,234)
Balance at Dec. 31, 2022	$ 923,766	436,538	694,862	(119,642)	(147,690)	864,068	59,698
Increase (Decrease) in Stockholders' Equity
Issuance of common shares per stock based compensation awards, shares	72,593
Common stock acquired for treasury, shares	149,819
Common stock dividend (in dollars per share)	$ 1.26
Net income	$ 124,934		124,927			124,927	7
Other comprehensive income (loss)	41,367				41,367	41,367
Issuance of 82,840, 72,593, and 63,527 common shares under stock based compensation awards for 2023, 2022 and 2021, respectively	3,806		2,184	1,622		3,806
Cost of 310,522, 149,819, and 713,132 shares of common stock acquired for treasury for 2023, 2022, and 2021, respectively	(12,469)			(12,469)		(12,469)
Common stock dividend ($1.30, $1.26, and $1.21 per share for 2023, 2022, and 2021, respectively)	(32,131)		(32,131)			(32,131)
Contributions from noncontrolling interests	20,343					0	20,343
Distributions to noncontrolling interests	(1,353)					0	(1,353)
Balance at Dec. 31, 2023	$ 1,068,263	$ 436,538	$ 789,842	$ (130,489)	$ (106,323)	$ 989,568	$ 78,695
Increase (Decrease) in Stockholders' Equity
Issuance of common shares per stock based compensation awards, shares	82,840
Common stock acquired for treasury, shares	310,522
Common stock dividend (in dollars per share)	$ 1.30