Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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

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No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (SX 210.5-02.22(a)(2))
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- Definition

Amount of the required periodic payments applied to principal.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

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

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No definition available.

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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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No definition available.

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- 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.

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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 210.5-02.19(b),22(b))
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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Long-Term Debt - Nordea Credit Agreement (Details) - USD ($) $ in Thousands	1 Months Ended		6 Months Ended		8 Months Ended
	Apr. 30, 2015	Sep. 30, 2014	Jun. 30, 2016	Jun. 30, 2015	Apr. 29, 2015
Debt Instrument [Line Items]
Funded amount			$ 0	$ 250,000
Nordea Q5000 Loan Maturing April 2020 [Member]
Debt Instrument [Line Items]
Borrowing capacity		$ 250,000
Funded amount	$ 250,000
Commitment fee percentage					0.875%
Maturity date		Apr. 30, 2020
Scheduled principal installments		$ 8,900
Frequency of periodic payment		quarterly
Balloon payment		$ 80,400
Nordea Q5000 Loan Maturing April 2020 [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Notional amount				$ 187,500
Nordea Q5000 Loan Maturing April 2020 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		2.50%
Minimum [Member] \| Nordea Q5000 Loan Maturing April 2020 [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Fixed LIBOR rate on interest rate swaps (as a percent)				1.49%
Maximum [Member] \| Nordea Q5000 Loan Maturing April 2020 [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Fixed LIBOR rate on interest rate swaps (as a percent)				1.52%