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LONG-TERM DEBT (Details) $ / shares in Units, $ in Millions |  |  |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
May 04, 2018 USD ($) $ / shares | Mar. 10, 2018 USD ($) | Dec. 05, 2017 USD ($) | Dec. 31, 2017 USD ($) Building $ / shares | May 03, 2018 Vessel | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2012 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  | $ 375.0 |  |  |  |
Maturity date |  |  |  | Nov. 30, 2020 |  |  |  |
Debt instrument, frequency of periodic payment |  |  |  | quarterly |  |  |  |
Debt instrument, periodic payment |  |  |  | $ 10.0 |  |  |  |
Number of new buildings | Building |  |  |  | 3 |  |  |  |
Percentage of purchase price expected to pay by lending provider |  |  |  | 77.50% |  |  |  |
Term of bareboat charter agreement |  |  |  | 10 years |  |  |  |
First flexibility period to purchase the vessels |  |  |  | 5 years |  |  |  |
Second flexibility period to purchase the vessels |  |  |  | 7 years |  |  |  |
Minimum value adjusted equity |  |  |  | $ 175.0 |  |  |  |
Minimum value adjusted equity ratio |  |  |  | 25.00% |  |  |  |
Minimum liquidity value |  |  |  | $ 20.0 |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of vessels placed in the market for sale | Vessel |  |  |  |  | 2 |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  |  | 10.50% |  |  |  |
Amount of dividends that can be distributed quarterly (in dollars per share) | $ / shares |  |  |  | $ 0.03 |  |  |  |
Maximum [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of additional vessels possibly expected to be sold | Vessel |  |  |  |  | 10 |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 500.0 | $ 430.0
Maturity date |  |  |  | Dec. 31, 2020 |  |  |  |
Deferred financing costs |  |  |  |  |  |  | $ 4.6 |
Drawn amount |  |  |  | $ 391.6 |  | $ 447.0 |  |
Percentage of increase in margin for the period of waiver |  |  |  |  |  | 2.00% |  |
Repayment of debt |  |  | $ 3.1 |  |  |  |  |
Revolving Credit Facility [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Security ratio after adjustment | 135.00% |  |  |  |  |  |  |
Liquidity covenant after adjustment | $ 15.0 |  |  |  |  |  |  |
Minimum market cap ratio after adjustment | $ 200.0 |  |  |  |  |  |  |
Percentage of increase in undrawn borrowings | 6.00% |  |  |  |  |  |  |
Dividend distributed | $ 4.3 |  |  |  |  |  |  |
Repayment of debt | $ 52.3 | $ 4.3 |  |  |  |  |  |
Amount of dividends that can be distributed quarterly (in dollars per share) | $ / shares | $ 0.03 |  |  |  |  |  |  |
Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Minimum market cap to value adjusted total assets |  |  |  | 25.00% |  |  |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Minimum market cap to value adjusted total assets |  |  |  | 45.00% |  |  |  |
Revolving Credit Facility [Member] | Maximum [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Proceeds from sale of equity | $ 75.0 |  |  |  |  |  |  |
New Revolving Credit Facility [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  | $ 250.0 |  |  |  |
Covenant amount |  |  |  | 30.0 |  |  |  |
New equity under recapitalization program |  |  |  | 103.7 |  |  |  |
Gross amount under new equity under recapitalization program |  |  |  | 110.0 |  |  |  |
Associated fees |  |  |  | 13.1 |  |  |  |
Financing of outstanding commitments per ship |  |  |  | 39.0 |  |  |  |
New Revolving Credit Facility [Member] | Bond Loan [Member] |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  | $ 150.0 |  |  |  |

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- Definition Refers to the first flexibility period to purchase the vessels as per agreement in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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