Real Estate Investments and Equity Method Investments - Schedule of Real Estate Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Real Estate Properties [Line Items]
Land	$ 197,777	$ 179,293
Land improvements	44,681	45,052
Buildings and improvements	690,120	677,293
Development and construction costs	61,859	6,649
Real estate investments	994,437	908,287	$ 633,591
Income producing property
Real Estate Properties [Line Items]
Land	175,885	171,733
Land improvements	44,681	45,052
Buildings and improvements	690,120	677,293
Development and construction costs	0	0
Real estate investments	910,686	894,078
Held for development
Real Estate Properties [Line Items]
Land	680	680
Land improvements	0	0
Buildings and improvements	0	0
Development and construction costs	0	0
Real estate investments	680	680
Construction in progress
Real Estate Properties [Line Items]
Land	21,212	6,880
Land improvements	0	0
Buildings and improvements	0	0
Development and construction costs	61,859	6,649
Real estate investments	$ 83,071	$ 13,529

Capitalized development and construction costs.

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- Definition

Amount of real estate investment property, excluding real estate investments held for sale.

+ References

No definition available.

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount before accumulated deprecation and depletion of additions or improvements to real estate held for productive use. Examples include, but are not limited to, walkways, driveways, fences, and parking lots.

+ References

No definition available.

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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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