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v3.20.1

SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Nov. 19, 2019 | Mar. 29, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Jun. 16, 2017
Authorized Shares [Roll forward] |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  | 360,000,000 |  |  |
Balance at end of period (in shares) |  |  | 360,000,000 | 360,000,000 |  |
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) |  | 5,260,968 |  |  |  |
Balance at end of period, issued (in shares) |  |  | 147,230,634 | 141,969,666 |  |
Balance at end of period, outstanding (in shares) |  |  | 147,230,634 | 141,969,666 |  |
Common Stock [Roll forward] |  |  |  |  |  |
Common Shares Issued in Follow-on Offering, value |  |  | $ 17,922 |  | $ 103,748 |
Common Stock [Abstract] |  |  |  |  |  |
Proceeds from issuance of common stock |  |  | 17,922 | $ 0 | 103,748 |
Additional Paid in Capital [Abstract] |  |  |  |  |  |
Reduction of share premium | $ (103,400) |  | 0 |  | $ 0 |
Share premium fund |  |  | 17,900 | 103,400 |  |
Contributed Surplus Account [Abstract] |  |  |  |  |  |
Reduction of contributed surplus |  |  | (308,800) |  |  |
Dividend paid |  |  | 14,300 | 9,900 |  |
Contribution to surplus account |  |  | $ 567,200 | $ 796,800 |  |
Shareholders' Rights Plan [Abstract] |  |  |  |  |  |
Common Share, par value (in dollars per share) |  |  | $ 0.01 | $ 0.01 |  |
Shareholders' Rights Agreement [Member] |  |  |  |  |  |
Shareholders' Rights Plan [Abstract] |  |  |  |  |  |
Preferred share purchase right |  |  |  |  |  | 0.001
Common Share, par value (in dollars per share) |  |  |  |  |  | $ 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) |  |  | 360,000,000 | 180,000,000 | 180,000,000 |
Authorization of additional authorized shares (in shares) |  |  |  | 180,000,000 |  |
Balance at end of period (in shares) |  |  | 360,000,000 | 360,000,000 | 180,000,000 |
Issued and Outstanding Shares [Roll forward] |  |  |  |  |  |
Balance at beginning of period, issued (in shares) |  |  | 141,969,666 | 141,969,666 | 101,969,666 |
Balance at beginning of period, outstanding (in shares) |  |  | 141,969,666 | 141,969,666 | 101,969,666 |
Common Shares Issued in Follow-on Offering (in shares) |  |  | 5,260,968 |  | 40,000,000 |
Balance at end of period, issued (in shares) |  |  | 147,230,634 | 141,969,666 | 141,969,666 |
Balance at end of period, outstanding (in shares) |  |  | 147,230,634 | 141,969,666 | 141,969,666 |
Common Stock [Roll forward] |  |  |  |  |  |
Balance at beginning of period |  |  | $ 1,420 | $ 1,420 | $ 1,020 |
Common Shares Issued in Follow-on Offering, value |  |  | 52 |  | 400 |
Balance at end of period |  |  | 1,472 | $ 1,420 | 1,420 |
Additional Paid in Capital [Abstract] |  |  |  |  |  |
Reduction of share premium |  |  | $ 0 |  | $ 0 |

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