Investment in Real Estate - Additional Information (Details) $ in Thousands, ft² in Millions	12 Months Ended
Dec. 31, 2017 USD ($) ft² Property	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Real Estate Properties [Line Items]
Number of industrial properties \| Property	488
Gross leasable area (GLA) of industrial properties \| ft²	60.2
Impairment of Real Estate \| $	$ 0	$ 0	$ 626
REIT Acquisition
Real Estate Properties [Line Items]
Number of industrial properties \| Property	1
Gross leasable area (GLA) of industrial properties \| ft²	0.2
Purchase Price \| $	$ 20,962
Percentage of Voting Interests Acquired	100.00%

Percentage of voting equity interests acquired at the acquisition date.

No definition available.

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- Definition

The amount of assets acquired.

+ References

No definition available.

+ Details

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- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ 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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