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Real Estate and Intangible Assets - Summary of Properties Acquired (Detail) $ in Thousands |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 17, 2019 USD ($) ft² property | Dec. 16, 2019 USD ($) ft² | Nov. 14, 2019 USD ($) ft² | Sep. 26, 2019 USD ($) ft² property | Jul. 30, 2019 USD ($) ft² | Jun. 18, 2019 USD ($) ft² | Apr. 30, 2019 USD ($) ft² | Apr. 05, 2019 USD ($) ft² property | Feb. 28, 2019 USD ($) ft² | Feb. 08, 2019 USD ($) ft² | Dec. 27, 2018 USD ($) ft² | Oct. 30, 2018 USD ($) ft² property shares | Sep. 20, 2018 USD ($) ft² | Mar. 09, 2018 USD ($) ft² | Dec. 31, 2019 USD ($) ft² | Dec. 31, 2018 USD ($) ft²
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 130,313 | $ 63,245
Acquisition Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,200 | $ 900
New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 69,650 |
Stated interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.90% |
Series of Property Acquisitions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,562,483 | 591,037
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 years 9 months 18 days | 11 years 1 month 6 days
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 130,313 | $ 63,245
Acquisition Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,231 | 905
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,009 | 5,984
Aggregate Mortgage Debt Issued or Assumed |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 37,410 | $ 11,663
Six Property Portfolio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² | 509,211 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term | 10 years 15 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price | $ 37,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent | $ 2,700 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties in portfolio | property | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Six Property Portfolio | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 19,500 |
Stated interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.75% |
Moorestown, New Jersey |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  | 26,050 |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  | 15 years 23 days |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  | $ 2,700 |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  |  |  | $ 200 |  |  |  |  |  |
Indianapolis, Indiana |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  | 231,509 |  |  |  |  |  | 34,800 |  |  |  |  |  |  |
Lease Term |  |  | 13 years 5 months 16 days |  |  |  |  |  | 10 years 1 day |  |  |  |  |  |  |
Aggregate Purchase Price |  |  | $ 8,200 |  |  |  |  |  | $ 3,600 |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  | $ 600 |  |  |  |  |  | $ 300 |  |  |  |  |  |  |
Ocala, Florida |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  | 383,000 |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  |  |  | 20 years 26 days |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  | $ 19,200 |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  | $ 1,500 |  |  |  |  |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Columbus, Ohio |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  | 54,430 |  |  |  |  |  | 157,810 |  |  |
Lease Term |  |  |  |  |  |  | 7 years |  |  |  |  |  | 15 years 11 days |  |  |
Aggregate Purchase Price |  |  |  |  |  |  | $ 3,200 |  |  |  |  |  | $ 8,500 |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  | $ 200 |  |  |  |  |  | 800 |  |  |
Columbus, Ohio | Interest rate swaps |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Mortgage Debt Issued or Assumed |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,700 |  |  |
Stated interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  | 3.22% |  |  |
Columbus, Ohio | LIBOR | Interest rate swaps |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  | 5.32% |  |  |
Tifton, Georgia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  | 676,031 |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  |  | 8 years 5 months 13 days |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  | $ 17,900 |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  | $ 1,600 |  |  |  |  |  |  |  |  |  |
Tifton, Georgia | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8,900 |
Denton, Texas |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  | 78,452 |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  |  | 11 years 11 months 1 day |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  |  | $ 6,600 |  |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  | $ 500 |  |  |  |  |  |  |  |  |  |  |
Temple, Texas |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  | 211,000 |  |  |  |  |  |  |  |  |  |  |  |
Lease Term |  |  |  | 20 years |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  |  |  | $ 14,100 |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  | $ 1,200 |  |  |  |  |  |  |  |  |  |  |  |
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 16 days |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price |  | $ 9,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent |  | $ 700 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Jackson, Tennessee | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,800 |
Stated interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.97% |
Carrollton, Georgia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² | 117,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease Term | 12 years 15 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price | $ 8,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Annualized GAAP Rent | $ 600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Carrollton, Georgia | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,200 |
Vance, Alabama |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  | 127,444 |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 years 9 months 18 days |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 14,300 |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,100 |  |
Detroit, Michigan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  |  | 218,703 |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  |  | 10 years 6 months |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  |  | $ 21,700 |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  |  |  |  |  | $ 1,700 |  |  |  |
Number of properties in portfolio | property |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |
Number of units issued in acquisition (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  | 742,937 |  |  |  |
Detroit, Michigan | New fixed rate mortgage notes payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Mortgage Debt Issued or Assumed |  |  |  |  |  |  |  |  |  |  |  | $ 6,900 |  |  |  |
Stated interest rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 4.63% |  |  |  |
Lake Mary, Florida |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  |  |  |  |  |  |  |  |  | 87,080 |  |  |  |  |
Lease Term |  |  |  |  |  |  |  |  |  |  | 11 years |  |  |  |  |
Aggregate Purchase Price |  |  |  |  |  |  |  |  |  |  | $ 18,700 |  |  |  |  |
Aggregate Annualized GAAP Rent |  |  |  |  |  |  |  |  |  |  | $ 2,400 |  |  |  |  |

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