Investment in Real Estate - Summary of Acquisition Purchase Price Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate [Line Items]
Land	$ 909,318	$ 864,813
Buildings and Improvements	2,704,850	2,521,457
Acquisition Activity
Real Estate [Line Items]
Land	79,347	92,810
Buildings and Improvements	81,747	73,028
Other Assets	1,225	1,659
Purchase price of industrial properties acquired	167,546	174,209	$ 111,130
Assumed Mortgage Loan (See Note 4)	(11,654)	0
Purchase Price, Net	155,892	174,209
Acquisition Activity \| In-Place Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(5,302)	(7,905)
Acquisition Activity \| Above Market Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(662)	(227)
Acquisition Activity \| Below Market Leases
Real Estate [Line Items]
Acquired Finite-lived Intangible Liabilities, Fair Value	$ (737)	$ (1,420)

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The amount of assets acquired.

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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.

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

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