RETIREMENT BENEFITS - Changes in Benefit Obligations and Plan Assets as Well as Funded Status of Retirement Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in plan assets
Fair value of plan assets at beginning of year	$ 1,024,454
Fair value of plan assets at end of year	764,405	$ 1,024,454
Pension Benefits
Change in benefit obligation
Obligation at beginning of year	925,129	971,415
Service cost	12,603	14,265	$ 13,638
Interest cost	20,579	17,697	23,074
Actuarial gains	(231,923)	(23,537)
Benefits paid	(44,443)	(43,512)
Participants’ contributions	0	0
Foreign currency exchange rate changes	(7,841)	(11,199)
Obligation at end of year	674,104	925,129	971,415
Change in plan assets
Fair value of plan assets at beginning of year	1,024,454	956,345
Actual return on plan assets	(218,002)	109,120
Employer contributions	2,396	2,501
Participants’ contributions	0	0
Benefits paid	(44,443)	(43,512)
Fair value of plan assets at end of year	764,405	1,024,454	956,345
Funded status	90,301	99,325
Amounts recognized in the consolidated balance sheets
Non-current assets	169,940	226,882
Current liabilities	(2,766)	(2,602)
Non-current liabilities	(76,873)	(124,955)
Net amount recognized	90,301	99,325
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss (gain)	209,874	161,837
Prior service cost (credit)	505	731
Net amount recognized	210,379	162,568
Other Postretirement Benefits
Change in benefit obligation
Obligation at beginning of year	19,525	22,152
Service cost	78	107	88
Interest cost	413	363	566
Actuarial gains	(3,609)	(1,631)
Benefits paid	(1,984)	(1,573)
Participants’ contributions	24	107
Foreign currency exchange rate changes	0	0
Obligation at end of year	14,447	19,525	22,152
Change in plan assets
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	1,960	1,466
Participants’ contributions	24	107
Benefits paid	(1,984)	(1,573)
Fair value of plan assets at end of year	0	0	$ 0
Funded status	(14,447)	(19,525)
Amounts recognized in the consolidated balance sheets
Non-current assets	0	0
Current liabilities	(1,421)	(1,460)
Non-current liabilities	(13,026)	(18,065)
Net amount recognized	(14,447)	(19,525)
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss (gain)	(6,002)	(2,690)
Prior service cost (credit)	(969)	(2,637)
Net amount recognized	$ (6,971)	$ (5,327)