Derivatives - Rate Cap Transaction narrative (Details) - Not Designated as Hedging Instrument [Member] - Interest rate cap [Member]	6 Months Ended	12 Months Ended
Jun. 30, 2016 USD ($) derivative_instrument	Dec. 31, 2015 USD ($)
Derivative [Line Items]
Number of derivative instruments \| derivative_instrument	1
Notional amount	$ 10,000,000	$ 10,000,000
Premium paid	70,000	70,000
Fair value	$ 3,000	$ 39,000
3-Month LIBOR [Member]
Derivative [Line Items]
Strike rate	2.00%	2.00%
Operating Expenses [Member]
Derivative [Line Items]
Change in fair value of derivative	$ 36,000	$ 31,000

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

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
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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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

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- 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.

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

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

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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.

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