EQUITY ROLL FORWARD (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Common Stock, Dividends, Per Share, Cash Paid	$ 0.195	$ 0.175	$ 0.390	$ 0.350
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance			$ 948,662
Net income	$ 59,763	$ 39,363	89,882	$ 67,526
Equity, ending balance	988,573		988,573
Temporary equity, beginning balance	106	(168)	(19)	(245)
Net income	170	(48)	289	28
Temporary Equity, Foreign Currency Translation Adjustments	8	7	14	8
Temporary equity, ending balance	284	(209)	284	(209)
Common Stock
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	4,635	4,641	4,648	4,622
Stock Issued During Period, Value, New Issues	3	12	4	26
Stock Repurchased and Retired During Period, Value	(15)	(9)	(38)	(15)
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	5	1	14	12
Equity, ending balance	4,628	4,645	4,628	4,645
Additional Paid in Capital
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	314,935	292,668	310,617	283,420
Stock Issued During Period, Value, New Issues	1,570	3,894	1,912	8,963
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	2,332	2,382	6,308	6,561
Equity, ending balance	318,837	298,944	318,837	298,944
Retained Earnings
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	861,156	779,456	859,817	764,562
Net income	59,364	39,141	89,129	67,021
Dividends, Common Stock, Cash	(9,076)	(8,177)	(18,205)	(16,320)
Stock Repurchased and Retired During Period, Value	(11,309)	(6,373)	(30,606)	(11,216)
Equity, ending balance	900,135	804,047	900,135	804,047
Minimum Pension Liability
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	(48,144)	(51,782)	(49,076)	(52,666)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	924	885	1,856	1,769
Equity, ending balance	(47,220)	(50,897)	(47,220)	(50,897)
Cumulative Translation Adjustment
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	(170,875)	(163,554)	(179,505)	(152,105)
Currency translation adjustment	(19,418)	8,114	(10,788)	(3,335)
Equity, ending balance	(190,293)	(155,440)	(190,293)	(155,440)
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	2,352	2,257	2,161	2,116
Net income	229	270	464	477
Currency translation adjustment	(95)	14	(139)	(52)
Equity, ending balance	2,486	2,541	2,486	2,541
Total Equity
Increase (Decrease) in Stockholders' Equity
Equity, beginning balance	964,059	863,686	948,662	849,949
Net income	59,593	39,411	89,593	67,498
Dividends, Common Stock, Cash	(9,076)	(8,177)	(18,205)	(16,320)
Stock Issued During Period, Value, New Issues	1,573	3,906	1,916	8,989
Stock Repurchased and Retired During Period, Value	(11,324)	(6,382)	(30,644)	(11,231)
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	2,337	2,383	6,322	6,573
Currency translation adjustment	(19,513)	8,128	(10,927)	(3,387)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	924	885	1,856	1,769
Equity, ending balance	$ 988,573	$ 903,840	$ 988,573	$ 903,840