Investments in Real Estate and Real Estate Under Construction - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) loan
Investments in Real Estate and Real Estate Under Construction [Line Items]
Below-market leases, net of accretion	$ 28,416	$ 28,967
Future accretion, year 1	2,034
Future accretion, year 2	2,026
Future accretion, year 3	1,719
Future accretion, year 4	1,620
Future accretion, year 5	1,528
Acquisition related costs	836	2,404
Investments in real estate under construction	106,652	95,402
Development Deals [Member]
Investments in Real Estate and Real Estate Under Construction [Line Items]
Capitalized interest	3,442	2,726
LCIF [Member]
Investments in Real Estate and Real Estate Under Construction [Line Items]
Below-market leases, net of accretion	64	96
Future accretion, year 1	32
Future accretion, year 2	32
Future accretion, year 3	0
Future accretion, year 4	0
Future accretion, year 5	0
Acquisition related costs	359	85
Investments in real estate under construction	$ 40,443	$ 9,223
Westmont, Illinios [Member]
Investments in Real Estate and Real Estate Under Construction [Line Items]
Impaired, number of loans \| loan		2
Westmont, Illinios [Member] \| LCIF [Member]
Investments in Real Estate and Real Estate Under Construction [Line Items]
Impaired, number of loans \| loan		2

Investments in Real Estate and Real Estate Under Construction [Line Items]

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Loans and Leases Receivable, Impaired, Number of Loans

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Amount of accumulated interest costs capitalized as part of property, plant and equipment cost basis.

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- Definition

Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: 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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