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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