DEBT (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 604,897	$ 661,095
Less current portion	(81,483)	(70,350)
Long-term portion	523,414	590,745
Sinosure Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	255,845	267,443
Unamortized discount and deferred finance costs	$ 2,071	2,262
10.75% Subordinated Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	10.75%
Term Loan [Member] \| 2017 Debt Facilities [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0	320,309
Unamortized discount and deferred finance costs		11,211
Term Loan [Member] \| ABN Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term debt	0	22,638
Unamortized discount and deferred finance costs		610
Term Loan [Member] \| Core Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term debt	285,688	0
Unamortized discount and deferred finance costs	4,836
Term Loan [Member] \| Transition Facility [Member]
Debt Instrument [Line Items]
Long-term debt	39,366	0
Unamortized discount and deferred finance costs	634
Senior Notes [Member] \| 8.5% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	23,998	23,858
Unamortized discount and deferred finance costs	$ 1,002	$ 1,142
Debt instrument, interest rate, stated percentage	8.50%	8.50%
Subordinated Debt [Member] \| 8.5% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	8.50%
Subordinated Debt [Member] \| 10.75% Subordinated Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 26,847
Unamortized discount and deferred finance costs		$ 1,084
Debt instrument, interest rate, stated percentage	10.75%	10.75%

Contractual interest rate for funds borrowed, under the debt agreement.

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