INCOME TAXES - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation from the tax computed at statutory income tax rates to the Company's income tax expense
Tax computed at statutory U.S. federal income tax rates									$ 20	$ 1,275	$ 11,286
Non-controlling interest									(851)	(648)	(1,114)
Foreign tax rate differential									1,866	(1,769)	(2,662)
Over (under) provided in prior periods									(520)	(244)	(4,683)
Nondeductible expenses									1,504	3,781	1,610
Benefit Attributable CARES Act									(3,064)
Capitalized transactions costs										19	62
Change in tax reserves									2,148	3,883	10,657
State Taxes, net of federal benefit									(409)	(429)	1,674
Change in valuation allowance									33	(35)	1,539
Investment Tax Credit									84	(1,215)
Refund Claim for Domestic Production Deduction											235
Tax Cuts and Jobs Act of 2017											(148)
Capital loss											15
Deferred income tax revaluation									(10)	(513)
Other, net											399
Total income tax expense (benefit)	$ 1,858	$ 92	$ (2,258)	$ 1,109	$ 1,332	$ 1,834	$ (274)	$ 1,213	$ 801	$ 4,105	$ 18,870