Fair Value of Financial Instruments (Details Textual) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate cash flow hedge reclassified as non-cash increase to interest expense in the next 12 months	$ 1.6
Originated Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate	4.60%
Minimum \| Assumed Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate	4.10%
Maximum \| Assumed Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate	4.70%
Weighted Average \| Assumed Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate	4.20%
Significant Other Observable Inputs (Level 2) \| Senior Notes 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	$ 248.5
Significant Other Observable Inputs (Level 2) \| Senior Notes Due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long term debt	261.9
Significant Unobservable Inputs (Level 3) \| Assumed Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of note payable	27.0
Significant Unobservable Inputs (Level 3) \| Originated Mortgage Notes Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of note payable	33.1
Senior Notes \| Significant Unobservable Inputs (Level 3) \| Senior Notes Due 2026
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	$ 192.8

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: 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=77997519&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

+ Details

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Balance Type:	credit
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 estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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Balance Type:	na
Period Type:	duration

- Definition

Fair value portion of notes payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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