STOCKHOLDERS' EQUITY - AOCI Changes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Changes in accumulated other comprehensive income, net of tax, by component
Balances	$ 1,222,733	$ 1,205,859	$ 1,242,363	$ 1,151,401
OTHER COMPREHENSIVE INCOME (LOSS), net of tax	(872)	183	(1,851)	(534)
Balances	1,231,538	1,211,361	1,231,538	1,211,361
Accumulated Other Comprehensive Income
Changes in accumulated other comprehensive income, net of tax, by component
Balances	3,345	6,386	4,324	7,103
Other comprehensive income (loss) before reclassifications			(1,479)	(40)
Amounts reclassified from accumulated other comprehensive income			(372)	(494)
OTHER COMPREHENSIVE INCOME (LOSS), net of tax	(872)	183	(1,851)	(534)
Balances	2,473	6,569	2,473	6,569
Unrecognized Net Periodic Benefit Credit
Changes in accumulated other comprehensive income, net of tax, by component
Balances			5,061	6,896
Amounts reclassified from accumulated other comprehensive income			(372)	(494)
OTHER COMPREHENSIVE INCOME (LOSS), net of tax			(372)	(494)
Balances	4,689	6,402	4,689	6,402
Interest Rate Swap
Changes in accumulated other comprehensive income, net of tax, by component
Balances			1,263	2,604
Other comprehensive income (loss) before reclassifications			(798)	(421)
OTHER COMPREHENSIVE INCOME (LOSS), net of tax			(798)	(421)
Balances	465	2,183	465	2,183
Foreign Currency Translation
Changes in accumulated other comprehensive income, net of tax, by component
Balances			(2,000)	(2,397)
Other comprehensive income (loss) before reclassifications			(681)	381
OTHER COMPREHENSIVE INCOME (LOSS), net of tax			(681)	381
Balances	$ (2,681)	$ (2,016)	$ (2,681)	$ (2,016)