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Investment in Real Estate Investment in Real Estate - Summary of Industrial Property Acquisitions (Details) $ in Thousands, ft² in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) ft² Property | Dec. 31, 2017 USD ($) ft² Property | Dec. 31, 2016 USD ($) ft² Property
Real Estate Properties [Line Items] |  |  |
Number of industrial properties | Property | 458 |  |
Gross leasable area (GLA) of industrial properties | ft² | 63.1 |  |
Acquisition Activity |  |  |
Real Estate Properties [Line Items] |  |  |
Number of industrial properties | Property | 10 | 8 | 6
Gross leasable area (GLA) of industrial properties | ft² | 1.0 | 1.1 | 0.7
Purchase price of industrial properties acquired | $ | $ 167,546 | $ 174,209 | $ 111,130

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- Definition The amount of assets acquired. + References No definition available. + Details
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- Definition Area of a real estate property. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | instant

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- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
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Balance Type: | na
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- Definition 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. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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- Details
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