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SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Jun. 16, 2017
Authorized Shares [Roll forward] |  |  |  |
Balance at beginning of period (in shares) | 180,000,000 |  |  |
Balance at end of period (in shares) | 360,000,000 | 180,000,000 |  |
Issued and Outstanding Shares [Roll forward] |  |  |  |
Balance at beginning of period, issued (in shares) | 141,969,666 |  |  |
Balance at beginning of period, outstanding (in shares) | 141,969,666 |  |  |
Common Shares Issued in Follow-on Offering (in shares) |  | 0 |  |
Balance at end of period, issued (in shares) | 141,969,666 | 141,969,666 |  |
Balance at end of period, outstanding (in shares) | 141,969,666 | 141,969,666 |  |
Common Stock [Roll forward] |  |  |  |
Equity incentive plan issuance |  |  | $ 1 |
Common Shares Issued in Follow-on Offering, value |  | $ 103,748 | 120,069 |
Common Stock [Abstract] |  |  |  |
Net proceeds from underwritten public offering of common shares | $ 0 | 103,748 | $ 120,068 |
Additional Paid in Capital [Abstract] |  |  |  |
Share premium fund | 103,400 | 103,400 |  |
Contributed Surplus Account [Abstract] |  |  |  |
Dividend paid | 9,900 | 59,100 |  |
Contribution to surplus account | $ 786,900 | $ 796,800 |  |
Shareholders' Rights Plan [Abstract] |  |  |  |
Preferred share purchase right | one preferred share purchase right to purchase one one-thousandth of a Series A Participating Preferred Share of the Company for each outstanding common share, par value $0.01 per share |  |  |
Common Share, par value (in dollars per share) | $ 0.01 | $ 0.01 |  | $ 0.01
Shareholders rights, exercise price (in dollars per share) |  |  |  | $ 30
Percentage of common share ownership |  |  |  | 15.00%
Common Stock [Member] |  |  |  |
Authorized Shares [Roll forward] |  |  |  |
Balance at beginning of period (in shares) | 180,000,000 | 180,000,000 | 180,000,000 |
Balance at end of period (in shares) | 360,000,000 | 180,000,000 | 180,000,000 |
Issued and Outstanding Shares [Roll forward] |  |  |  |
Balance at beginning of period, issued (in shares) | 141,969,666 | 101,969,666 | 89,182,001 |
Balance at beginning of period, outstanding (in shares) | 141,969,666 | 101,969,666 | 89,182,001 |
Equity incentive plan issuance (in shares) |  |  | 137,665 |
Common Shares Issued in Follow-on Offering (in shares) |  | 40,000,000 | 12,650,000 |
Authorization of additional authorized shares (in shares) | 180,000,000 |  |  |
Balance at end of period, issued (in shares) | 141,969,666 | 141,969,666 | 101,969,666 |
Balance at end of period, outstanding (in shares) | 141,969,666 | 141,969,666 | 101,969,666 |
Common Stock [Roll forward] |  |  |  |
Balance at beginning of period | $ 1,420 | $ 1,020 | $ 892 |
Equity incentive plan issuance |  |  | 1 |
Common Shares Issued in Follow-on Offering, value |  | 400 | 127 |
Balance at end of period | $ 1,420 | $ 1,420 | $ 1,020 |

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