v3.19.1

RECENTLY ADOPTED ACCOUNTING STANDARDS RECENTLY ADOPTED ACCOUNING STANDARDS (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to opening balance				$ 0
Debt prepayment costs	$ 3,001	$ 402	$ 3,001	0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect		32,155	(6,921)	(1,314)
Cash, Cash Equivalents, and Restricted Cash		$ 33,704	1,549	8,470	$ 9,784
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to opening balance					(3,255)
Accounting Standards Update 2014-09 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt prepayment costs			0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect			0	0
Cash, Cash Equivalents, and Restricted Cash			0	0	0
Accounting Standards Update 2016-15 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt prepayment costs			3,001
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect			0	0
Cash, Cash Equivalents, and Restricted Cash			0	0	0
Accounting Standards Update 2016-18 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt prepayment costs			0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect			3,525	3,530
Cash, Cash Equivalents, and Restricted Cash			$ 481	4,006	476
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to opening balance				$ (120)
Retained Earnings [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to opening balance					$ (3,255)

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