CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Shares	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Non-controlling Interest
Beginning balance (in shares) at Dec. 31, 2017		128,970,776
Beginning balance at Dec. 31, 2017	$ 1,692,940	$ 872,228	$ 707,378	$ 13,417	$ 99,917
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	42,706		40,539		2,167
Dividends ($0.27, $0.27, $0.25, and $0.27 per share, respectively)	(32,634)		(32,634)
Issuance of shares under incentive stock plans (in shares)		204,336
Issuance of shares under incentive stock plans	5,455	$ 5,455
Stock-based compensation	1,262	$ 1,262
Repurchase of common shares (in shares)		(811)
Repurchase of common shares	(18)	$ (18)
Amortization of pension and postretirement plan liabilities	159			159
Foreign currency translation adjustment	9,688			7,606	2,082
Cash flow hedges	16,615			16,381	234
Ending balance (in shares) at Mar. 31, 2018		129,174,301
Ending balance at Mar. 31, 2018	1,736,173	$ 878,927	715,283	37,563	104,400
Beginning balance (in shares) at Dec. 31, 2017		128,970,776
Beginning balance at Dec. 31, 2017	1,692,940	$ 872,228	707,378	13,417	99,917
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	82,043
Amortization of pension and postretirement plan liabilities	338
Foreign currency translation adjustment	(20,072)
Cash flow hedges	17,143
Ending balance (in shares) at Jun. 30, 2018		129,451,268
Ending balance at Jun. 30, 2018	1,712,877	$ 880,560	716,328	16,601	99,388
Beginning balance (in shares) at Mar. 31, 2018		129,174,301
Beginning balance at Mar. 31, 2018	1,736,173	$ 878,927	715,283	37,563	104,400
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	39,338		36,258		3,080
Dividends ($0.27, $0.27, $0.25, and $0.27 per share, respectively)	(35,213)		(35,213)
Issuance of shares under incentive stock plans (in shares)		357,139
Issuance of shares under incentive stock plans	2,369	$ 2,369
Stock-based compensation	2,212	$ 2,212
Repurchase of common shares (in shares)		(80,172)
Repurchase of common shares	(2,948)	$ (2,948)
Amortization of pension and postretirement plan liabilities	178			178
Foreign currency translation adjustment	(29,760)			(22,857)	(6,903)
Cash flow hedges	529			1,717	(1,189)
Ending balance (in shares) at Jun. 30, 2018		129,451,268
Ending balance at Jun. 30, 2018	1,712,877	$ 880,560	716,328	16,601	99,388
Beginning balance (in shares) at Dec. 31, 2018		129,488,675
Beginning balance at Dec. 31, 2018	1,654,550	$ 884,263	672,371	239	97,677
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,793		24,794		2,999
Dividends ($0.27, $0.27, $0.25, and $0.27 per share, respectively)	(35,049)		(35,049)
Issuance of shares under incentive stock plans (in shares)		26,031
Issuance of shares under incentive stock plans	597	$ 597
Stock-based compensation	1,477	$ 1,477
Repurchase of common shares (in shares)		(1,140)
Repurchase of common shares	(33)	$ (33)
Amortization of pension and postretirement plan liabilities	112			112
Foreign currency translation adjustment	6,033			4,680	1,353
Cash flow hedges	(10,686)			(10,884)	198
Distribution to minority shareholder	(3,594)				(3,594)
Ending balance (in shares) at Mar. 31, 2019		129,513,566
Ending balance at Mar. 31, 2019	1,641,200	$ 886,304	662,116	(5,853)	98,633
Beginning balance (in shares) at Dec. 31, 2018		129,488,675
Beginning balance at Dec. 31, 2018	1,654,550	$ 884,263	672,371	239	97,677
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	48,713
Amortization of pension and postretirement plan liabilities	224
Foreign currency translation adjustment	429
Cash flow hedges	(30,205)
Ending balance (in shares) at Jun. 30, 2019		129,629,716
Ending balance at Jun. 30, 2019	1,600,298	$ 884,618	645,743	(29,511)	99,448
Beginning balance (in shares) at Mar. 31, 2019		129,513,566
Beginning balance at Mar. 31, 2019	1,641,200	$ 886,304	662,116	(5,853)	98,633
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,920		18,752		2,168
Dividends ($0.27, $0.27, $0.25, and $0.27 per share, respectively)	(35,125)		(35,125)
Issuance of shares under incentive stock plans (in shares)		250,344
Issuance of shares under incentive stock plans	177	$ 177
Stock-based compensation	2,344	$ 2,344
Repurchase of common shares (in shares)		(134,194)
Repurchase of common shares	(4,207)	$ (4,207)
Amortization of pension and postretirement plan liabilities	112			112
Foreign currency translation adjustment	(5,604)			(4,305)	(1,299)
Cash flow hedges	(19,519)			(19,465)	(54)
Ending balance (in shares) at Jun. 30, 2019		129,629,716
Ending balance at Jun. 30, 2019	$ 1,600,298	$ 884,618	$ 645,743	$ (29,511)	$ 99,448