Investment in Real Estate - Summary of Acquisition Purchase Price Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Real Estate [Line Items]
Land	$ 957,478	$ 909,318
Buildings and Improvements	2,782,430	2,704,850
Acquisition Activity
Real Estate [Line Items]
Land	101,764	79,347
Buildings and Improvements	43,693	81,747
Other Assets	859	1,225
Purchase price of industrial properties acquired	147,887	167,546	$ 174,209
Assumed Mortgage Loan (See Note 4)	0	(11,654)
Purchase Price, Net	147,887	155,892
Acquisition Activity \| In-Place Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(5,601)	(5,302)
Acquisition Activity \| Above Market Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(34)	(662)
Acquisition Activity \| Below Market Leases
Real Estate [Line Items]
Acquired Finite-lived Intangible Liabilities, Fair Value	$ (4,064)	$ (737)

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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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