SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Restricted cash and cash equivalents, noncurrent	$ 16,398	$ 58,630	$ 16,398	$ 58,630	$ 60,572
Amortization of financing costs	$ 700	$ 1,300	$ 1,600	$ 2,500
Credit losses historical period			5 years
Credit losses outstanding additional period			180 days
10.75% Subordinated Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt instrument, interest rate, stated percentage	10.75%		10.75%
2020 Debt Facilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	$ 7,300		$ 7,300
Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			95.00%		88.00%
Term Loan [Member] | Core Term Loan Facility, Core Transition Facility, Sinosure Credit Facility and 8.5% Senior Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	8,500		$ 8,500		$ 16,300
Term Loan [Member] | Core Revolving Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	800		800
Revolving Credit Facility [Member] | INSW Facilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross					$ 300
Revolving Credit Facility [Member] | Core Revolving Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred finance costs, gross	$ 900		$ 900