Derivatives - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Mortgage Loans \| LIBOR
Derivative [Line Items]
Basis spread on variable rate for debt	1.325%	1.325%
Interest Rate Cap
Derivative [Line Items]
Premium paid on derivative for right to receive cash payments	$ 2,000
Floor interest rate on derivative	2.35%
Cap interest rate on derivative	3.675%
Interest Rate Cap \| Other assets
Derivative [Line Items]
Derivative asset, notional amount	$ 35,000	$ 35,000

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

No definition available.

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- Definition

Amount, after accumulated amortization, of debt premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

+ Details

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- 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=84234895&loc=SL5579245-113959

Reference 2: 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=84234895&loc=SL5580258-113959

+ Details

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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.

+ Details

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- Definition

Floor rate on an interest rate derivative such as an interest rate floor or collar. If market rates falls below the floor rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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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.

+ Details

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- Details

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- Details

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- Details

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