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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-Name Accounting Standards Codification

-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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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

High end of the range of percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

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Low end of the range of percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

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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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-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

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-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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Long-Term Debt (Nordea Credit Agreement) (Details) - USD ($) $ in Thousands	1 Months Ended		8 Months Ended	9 Months Ended
	Apr. 30, 2015	Sep. 30, 2014	Apr. 29, 2015	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015
Debt Instrument [Line Items]
Funded amount				$ 250,000	$ 0
Nordea Q5000 Loan [Member]
Debt Instrument [Line Items]
Original borrowing capacity		$ 250,000			250,000
Funded amount	$ 250,000
Commitment fee percentage			0.875%
Debt instrument, maturity date		Apr. 30, 2020
Debt instrument, periodic payment, principal		$ 8,900
Debt instrument, frequency of periodic payment		quarterly
Debt instrument, periodic payment terms, balloon payment to be paid		$ 80,400			$ 80,400
Nordea Q5000 Loan [Member] \| Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Derivative, lower range of basis spread on variable rate						1.49%
Derivative, higher range of basis spread on variable rate						1.52%
Derivative, notional amount						$ 187,500
Nordea Q5000 Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		2.50%