POSTRETIREMENT BENEFITS (obligations and funded status) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in benefit obligation
Interest cost		$ 968	$ 1,911	$ 2,727
Change in plan assets
Fair value of plan assets, beginning of year		139,372
Fair value of plan assets, end of year		144,800	139,372
Amounts recognized on the consolidated balance sheets
Other non-current assets		87,019	71,208
Amounts recognized in accumulated other comprehensive loss
Unrecognized prior service credit		9,914	11,335
Unrecognized net actuarial loss		(25,445)	(35,454)
Tax effect		100	2,163
Amount recognized in accumulated other comprehensive loss, net of tax		(15,431)	(21,956)
Postretirement benefit plan [Member]
Change in benefit obligation
Benefit obligation, beginning of year		68,164	73,175
Interest cost		929	1,835
Net actuarial (gain) loss		(5,721)	218
Benefits paid from plan assets and company funds		(5,591)	(7,064)
Benefit obligation, end of year		57,781	68,164	73,175
Change in plan assets
Fair value of plan assets, beginning of year		139,372	129,918
Return on plan assets		10,159	15,741
Benefits paid		(4,731)	(6,287)
Fair value of plan assets, end of year		144,800	139,372	129,918
Funded status		87,019	71,208
Amounts recognized on the consolidated balance sheets
Other non-current assets		$ 87,019	71,208
Amounts recognized in accumulated other comprehensive loss
Amortization period net actuarial loss		12 years 6 months
Pension plan [Member]
Change in benefit obligation
Benefit obligation, beginning of year	[1]	$ 3,343	3,251
Interest cost		39	76
Net actuarial (gain) loss		2	340
Benefits paid from plan assets and company funds		(324)	(324)
Benefit obligation, end of year	[1]	3,060	3,343	3,251
Change in plan assets
Fair value of plan assets, beginning of year		0	0
Fair value of plan assets, end of year		0	0	$ 0
Funded status		(3,060)	(3,343)
Amounts recognized on the consolidated balance sheets
Accrued liabilities		324	324
Other non-current liabilities		$ 2,736	$ 3,019

[1] The accumulated benefit obligation equals the projected benefit obligation