Derivatives - Summary of rate cap agreement (Details) - Interest rate cap [Member] - Not Designated as Hedging Instrument [Member] - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Notional Amount	$ 10,000,000	$ 10,000,000
Premium Paid	70,000	70,000
Unamortized premium	70,000	70,000
Fair value	3,000	39,000
Cumulative Cash Flows Received	$ 0	$ 0
3-Month LIBOR [Member]
Derivative [Line Items]
3-Month LIBOR Strike Rate	2.00%	2.00%

Derivative Asset, Cumulative Cash Received

No definition available.

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- Definition

Derivative Asset, Unamortized Premium

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: 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=56946850&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: 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=56946850&loc=SL5580258-113959

+ Details

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Period Type:	instant

- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 55
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-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313

+ Details

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

- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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Period Type:	instant

- 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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- Definition

The cash outflow for derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3505-108585

+ Details

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Balance Type:	credit
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- Details

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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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