Number of required installments under the debt agreement.

No definition available.

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- Definition

The number of vessels mortgaged to a bank for securing the debt with that bank.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- 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.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

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- 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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Amount of the required periodic payments applied to principal.

+ References

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- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

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- 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.

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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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Long-term debt, current and non-current, textuals 2 (Details) $ in Thousands				6 Months Ended
	May 21, 2021 USD ($)	May 20, 2021	Mar. 30, 2015 USD ($)	Jun. 30, 2021 USD ($) installment item	Dec. 31, 2020 USD ($) item
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis				LIBOR plus margin
Number Of Vessels Collateral For Debt \| item				30	30
Debt Instrument Collateral Amount				$ 615,327
Minimum cash deposits required to be maintained				$ 18,500	$ 20,000
Minimum [Member]
Debt Instrument [Line Items]
Loan Margin Percentage				2.15%
Maximum [Member]
Debt Instrument [Line Items]
Loan Margin Percentage				2.50%
Export-Import Bank of China and DnB NOR Bank ASA [Member] \| Secured Debt [Member] \| First Tranche [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date				Feb. 15, 2012
Proceeds From Issuance Of Secured Debt				$ 37,450
Debt Instrument, Number of installments \| installment				40
Debt Instrument, Frequency of Periodic Payments				quarterly
Debt Instrument, Periodic Payment, Principal				$ 628
Debt Instrument, Balloon Payment				$ 12,332
Debt Instrument, Maturity Date				Feb. 15, 2022
Export-Import Bank of China and DnB NOR Bank ASA [Member] \| Secured Debt [Member] \| Second Tranche [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date				May 18, 2012
Proceeds From Issuance Of Secured Debt				$ 34,640
Debt Instrument, Number of installments \| installment				40
Debt Instrument, Frequency of Periodic Payments				quarterly
Debt Instrument, Periodic Payment, Principal				$ 581
Debt Instrument, Balloon Payment				$ 11,410
Debt Instrument, Maturity Date				May 18, 2022
Loan Margin Percentage				2.50%
ABN AMRO Bank N.V. [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Proceeds From Issuance Of Secured Debt	$ 91,000		$ 50,160
Debt Instrument, Number of installments \| installment				24
Debt Instrument, Frequency of Periodic Payments				quarterly
Debt Instrument, Periodic Payment, Principal				$ 994
Debt Instrument, Balloon Payment				$ 26,310
Debt Instrument, Maturity Date				May 20, 2026
Debt Instrument, Description of Variable Rate Basis		LIBOR		LIBOR
Loan Margin Percentage				2.00%