Fixed interest rate related to the interest rate derivative.

No definition available.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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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

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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- Definition

Fair value of asset after deduction of liability.

+ References

No definition available.

+ Details

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Derivative Instruments and Fair Value Measurements (Details Textual)	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Number of Instruments Held \| swap							1
Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed Interest Rate							6.63%
Forward Contracts [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative gain (loss)	$ (379,000)		$ (696,000)
Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative gain (loss)	(319,000)	$ (156,000)	(265,000)	$ (1,109,000)
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value, Net Asset (Liability)						$ (104,000)
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value, Net Asset (Liability)	675,275		675,275		$ (20,950)
Fair Value, Measurements, Recurring [Member] \| Swap [Member] \| Fuel [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value, Net Asset (Liability)	$ 38,319		$ 38,319		$ 303,675