Condensed Consolidated Statements of Changes in Retained Earnings And Accumulated Other Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 58,396	$ 69,613	$ 215,859	$ 191,991
Pension and post-retirement plan adjustments, net of tax benefit	313	308	954	751
Unrecognized net loss on cash flow hedges (Note 7)	(5)	0	(50)	0
Reclassification from accumulated other comprehensive loss into net income (Note 7)	115	0	82	0
Preferred dividends	(10)	(10)	(30)	(30)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,662,279	1,431,147	1,546,230	1,349,650
Net income	58,396	69,613	215,859	191,991
Common dividends	(20,824)	(20,747)	(62,218)	(61,608)
Preferred dividends	(10)	(10)	(30)	(30)
Ending balance	1,699,841	1,480,003	1,699,841	1,480,003
Accumulated Other Comprehensive (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(49,480)	(74,526)	(41,781)	(141,649)
Foreign currency translation adjustments	(380)	(1,631)	(8,642)	65,049
Pension and post-retirement plan adjustments, net of tax benefit	313	308	954	751
Unrecognized net loss on cash flow hedges (Note 7)	(5)		(50)
Reclassification from accumulated other comprehensive loss into net income (Note 7)	115		82
Ending balance	$ (49,437)	$ (75,849)	$ (49,437)	$ (75,849)