Investment in Real Estate Investment in Real Estate - Summary of Purchase Price Allocation (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Real Estate [Line Items]
Land	$ 870,151	$ 794,821
Buildings and Improvements	2,554,194	$ 2,523,015
Acquisition Activity
Real Estate [Line Items]
Land	90,429
Buildings and Improvements	61,973
Other Assets	1,195
Purchase price of industrial properties acquired	158,974
Acquisition Activity \| In-Place
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	$ (6,670)
Acquired finite lived intangible assets, weighted average life	70 months
Acquisition Activity \| Above Market Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	$ (127)
Acquired finite lived intangible assets, weighted average life	34 months
Acquisition Activity \| Below Market Leases
Real Estate [Line Items]
Acquired finite lived intangible liabilities, fair value	$ (1,420)
Acquired finite-lived intangible liabilities, weighted average useful life	85 months

Acquired Finite-lived Intangible Liabilities, Weighted Average Useful Life

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Finite-lived Intangible Liabilities Acquired

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The amount of assets acquired.

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No definition available.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount of assets classified as other.

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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.

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No definition available.

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