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Real Estate and Intangible Assets - Summary of Acquired Properties (Details) $ in Thousands |  |  |  | 3 Months Ended
--- | --- | --- | --- | ---
Mar. 09, 2019 USD ($) ft² | Feb. 28, 2019 USD ($) ft² | Feb. 08, 2019 USD ($) ft² | Mar. 31, 2019 USD ($) ft² | Mar. 31, 2018 USD ($) ft²
Business Acquisition [Line Items] |  |  |  |  |
Purchase Price |  |  |  | $ 6,315 | $ 14,341
Philadelphia, Pennsylvania |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Square Footage | ft² |  |  | 26,050 |  |
Lease Term |  |  | 15 years 23 days |  |
Purchase Price |  |  | $ 2,700 |  |
Annualized GAAP Rent |  |  | $ 200 |  |
Indianapolis, Indiana |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Square Footage | ft² |  | 34,800 |  |  |
Lease Term |  | 10 years 1 day |  |  |
Purchase Price |  | $ 3,600 |  |  |
Annualized GAAP Rent |  | $ 300 |  |  |
Vance, Alabama |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Square Footage | ft² | 127,444 |  |  |  |
Lease Term | 9 years 9 months 18 days |  |  |  |
Purchase Price | $ 14,300 |  |  |  |
Annualized GAAP Rent | $ 1,100 |  |  |  |
Series of Property Acquisitions |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Square Footage | ft² |  |  |  | 60,850 | 127,444
Lease Term |  |  |  | 12 years 2 months 12 days | 9 years 9 months 18 days
Purchase Price |  |  |  | $ 6,315 | $ 14,341
Acquisition Expenses |  |  |  | 100 | 100
Annualized GAAP Rent |  |  |  | $ 516 | $ 1,087

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