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Real Estate and Intangible Assets - Summary of Properties Acquired (Detail) $ in Thousands |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 21, 2020 USD ($) ft² tenant | Dec. 18, 2020 USD ($) ft² tenant | Oct. 14, 2020 USD ($) ft² tenant | Sep. 01, 2020 USD ($) ft² tenant | Mar. 09, 2020 USD ($) ft² tenant | Jan. 27, 2020 USD ($) ft² property | Jan. 08, 2020 USD ($) ft² tenant | Dec. 17, 2019 USD ($) ft² property tenant | Dec. 16, 2019 USD ($) ft² tenant | Nov. 14, 2019 USD ($) ft² tenant | Sep. 26, 2019 USD ($) ft² property tenant | Jul. 30, 2019 USD ($) ft² tenant | Jun. 18, 2019 USD ($) ft² tenant | Apr. 30, 2019 USD ($) ft² tenant | Apr. 05, 2019 USD ($) ft² tenant property | Feb. 28, 2019 USD ($) ft² tenant | Feb. 08, 2019 USD ($) ft² tenant | Dec. 31, 2020 USD ($) ft² property | Dec. 31, 2019 USD ($) ft² property
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties acquired | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 | 18
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 129,974 | $ 130,313
Series of Property Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,717,502 | 2,562,483
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 years 2 months 12 days | 12 years 9 months 18 days
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 129,974 | $ 130,313
Acquisition Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 814 | $ 1,231
Six Property Portfolio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  | 509,211 |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  | $ 37,600 |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  |  |  | 6 |  |  |  |  |  |  |  |  |  |  |
Indianapolis, Indiana |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  | 64,800 |  |  | 231,509 |  |  |  |  |  | 34,800 |  |  |
Lease Term |  |  |  |  |  |  | 7 years 2 months 12 days |  |  | 13 years 6 months |  |  |  |  |  | 10 years |  |  |
Aggregate Purchase Price |  |  |  |  |  |  | $ 5,300 |  |  | $ 8,200 |  |  |  |  |  | $ 3,600 |  |  |
Number of tenants | tenant |  |  |  |  |  |  | 3 |  |  | 1 |  |  |  |  |  | 1 |  |  |
Houston, Texas; Charlotte, North Carolina; St. Charles, Missouri |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  | 320,838 |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  | 20 years |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  | $ 34,700 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |
Crandall, Georgia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  | 504,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  | 10 years 6 months |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  | $ 32,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Terre Haute, Indiana |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  | 153,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  | 9 years 8 months 12 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  | $ 10,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Montgomery, Alabama |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  | 240,714 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  | 7 years 2 months 12 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  | $ 14,300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Huntsville, Alabama |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  | 277,883 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  | 9 years 2 months 12 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  | $ 20,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pittsburgh, Pennsylvania |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² | 155,267 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price | $ 13,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Moorestown, New Jersey |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 26,050 |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15 years 1 month 6 days |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,700 |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |
Ocala, Florida |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 383,000 |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20 years 1 month 6 days |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 19,200 |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |
Columbus, Ohio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  | 54,430 |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  | 7 years |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,200 |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |
Tifton, Georgia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  | 676,031 |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  | 8 years 6 months |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  | $ 17,900 |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |
Denton, Texas |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  | 78,452 |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  | 11 years 10 months 24 days |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  | $ 6,600 |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |
Temple, Texas |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  | 211,000 |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  | 20 years |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  | $ 14,100 |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Jackson, Tennessee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  | 241,000 |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  | 9 years 8 months 12 days |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  | $ 9,100 |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |
Carrollton, Georgia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  | 117,000 |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  | 12 years |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  | $ 8,100 |  |  |  |  |  |  |  |  |  |  |
Number of tenants | tenant |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |

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