Investment in Real Estate - Summary of Acquisition Purchase Price Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Real Estate [Line Items]
Land	$ 864,813	$ 794,821
Buildings and Improvements	2,521,457	2,523,015
Acquisition Activity
Real Estate [Line Items]
Land	92,810	70,380
Buildings and Improvements	73,028	37,031
Other Assets	1,659	781
Assumed Mortgage Loan Premium (See Note 4)	0	(529)
Purchase price of industrial properties acquired	174,209	111,130	$ 169,218
Assumed Mortgage Loan (See Note 4)	0	(4,513)
Purchase Price, Net	174,209	106,617
Acquisition Activity \| In-Place Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(7,905)	(3,253)
Acquisition Activity \| Above Market Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(227)	(214)
Acquisition Activity \| Below Market Leases
Real Estate [Line Items]
Acquired Finite-lived Intangible Liabilities, Fair Value	$ 1,420	$ 0

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The amount of assets acquired.

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Purchase Price, Net

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Recognized Identifiable Assets Acquired and Liabilities Assumed Noncurrent Liabilities Long term Debt Fair Value Adjustment

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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