Investment in Real Estate Investment in Real Estate - Summary of Purchase Price Allocation (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Real Estate [Line Items]
Land	$ 888,466	$ 864,813
Buildings and Improvements	2,579,886	$ 2,521,457
Acquisition Activity
Real Estate [Line Items]
Land	50,262
Buildings and Improvements	45,393
Other Assets	526
Purchase price of industrial properties acquired	98,000
Assumed Mortgage Loan (Note 4)	11,654
Purchase Price, Net	86,346
Acquisition Activity \| In-Place Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(2,483)
Acquisition Activity \| Above Market Leases
Real Estate [Line Items]
Acquired finite lived intangible assets, fair value	(73)
Acquisition Activity \| Below Market Leases
Real Estate [Line Items]
Acquired finite lived intangible liabilities, fair value	$ (737)

Finite-lived Intangible Liabilities Acquired

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The amount of assets acquired.

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Purchase Price, Net

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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

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-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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