Represents the percentage of debt instrument paid in kind.

No definition available.

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- Definition

The amount of excess cash flow used to paydown outstanding debt classified as current.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Period of excess cash flow to be paid to lender from the end of reporting period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Interest paid other than in cash for example by issuing additional debt securities.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents vessel age repayment period.

+ References

No definition available.

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- Definition

Line of credit facility covenant cash flow sweep As percentage of excess cash from collateralized vessels.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate fair value of the mortgaged vessels to be maintained as a percentage of aggregate outstanding principal amount as per the terms of the credit facilities' covenants.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility covenant option one cash flow sweep as percentage of excess cash from collateralized vessels.

+ References

No definition available.

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- Definition

Amount of line of credit facility prepayment under cash sweep required for initial aggregate prepayment amount.

+ References

No definition available.

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- Definition

Amount of line of credit facility covenant threshold initial aggregate prepayments limit for prepayment under cash sweep.

+ References

No definition available.

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- Definition

Amount of line of credit facility future amortization payments per quarter per facility agreement. Upon payment of excess cash flow to lenders, these amortization payments shall be adjusted.

+ References

No definition available.

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- Definition

Represents the minimum cash balance per vessel required to be maintained for vessels owned under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of long-term debt including PIK interest, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Represents the maximum ratio of total debt outstanding to total capitalization.

+ References

No definition available.

+ Details

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- Definition

Minimum working capital required per terms of the credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the number of remaining vessels to be sold.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents the number of vessels mortgaged by the entity as collateral in support of agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents cash outflow for PIK interest.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of line of credit facility repayment for the excess cash flow sweep covenant required during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Repayments of secured debt, including paid in kind interest.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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DEBT - $400 Million Credit Facility (Details) $ in Thousands			12 Months Ended
	Nov. 14, 2016 USD ($)	Nov. 10, 2016 USD ($) item	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)
Line of Credit Facility
PIK interest				$ 5,341
Restricted cash, non-current			$ 315	23,233	$ 27,426	$ 315
Payment of PIK interest			5,341	0	0
Secured Debt \| $400 Million Credit Facility
Line of Credit Facility
Maximum borrowing capacity		$ 400,000		400,000	$ 400,000
Number of vessels mortgaged \| item		45
Number of remaining vessels to be sold \| item					5
Drawdowns during the period	$ 400,000				$ 400,000
PIK interest			0	5,341
PIK interest (as a percent)		1.50%
Maximum total indebtedness to total capitalization (as a ratio)		0.70
Minimum working capital required		$ 0
Excess cash flow sweep				$ 11,334
Excess cash flow sweep period				45 days
Repayments for the excess cash flow sweep			15,428	$ 0
Restricted cash, non-current				11,180
Repayment of secured debt			399,600	400	$ 0
Repayments of debt, including PIK			404,941
Payment of PIK interest			5,341
Long-term debt including PIK interest			$ 0	$ 398,609
Secured Debt \| $400 Million Credit Facility \| Through December 31, 2018
Line of Credit Facility
Amortization payments per quarter		100
Minimum cash balance required per vessel owned		$ 250
Cash flow sweep (as a percent)		100.00%
Secured Debt \| $400 Million Credit Facility \| From March 31, 2019 through December 31, 2020
Line of Credit Facility
Amortization payments per quarter		$ 7,610
Secured Debt \| $400 Million Credit Facility \| From March 31, 2021 through September 30, 2021
Line of Credit Facility
Amortization payments per quarter		18,571
Secured Debt \| $400 Million Credit Facility \| Period Upon Final Maturity On November 15 2021
Line of Credit Facility
Amortization payments per quarter		$ 282,605
Secured Debt \| $400 Million Credit Facility \| From June 30, 2018 to December 30, 2018
Line of Credit Facility
Collateral security maintenance test (as a percent)		105.00%
Secured Debt \| $400 Million Credit Facility \| From December 31, 2018 to December 30, 2020
Line of Credit Facility
Collateral security maintenance test (as a percent)		115.00%
Cash flow sweep (as a percent)		75.00%
Prepayment under cash sweep required		$ 0
Threshold initial aggregate prepayments limit for prepayment under cash sweep		$ 10,000
Secured Debt \| $400 Million Credit Facility \| After December 30, 2020
Line of Credit Facility
Collateral security maintenance test (as a percent)		135.00%
Secured Debt \| $400 Million Credit Facility \| After December 31, 2020
Line of Credit Facility
Cash flow sweep option one (as a percent)		50.00%
Vessel age repayment period		15 years
Secured Debt \| $400 Million Credit Facility \| From January 1, 2019 To December 31, 2019
Line of Credit Facility
Minimum cash balance required per vessel owned		$ 400
Secured Debt \| $400 Million Credit Facility \| After January 1, 2020
Line of Credit Facility
Minimum cash balance required per vessel owned		$ 700
Secured Debt \| $400 Million Credit Facility \| LIBOR
Line of Credit Facility
Reference rate		three-month LIBOR
Applicable margin over reference rate (as a percent)		3.75%