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Mortgage Notes Payable and Credit Facility - Mortgages Notes Payable (Detail) $ in Thousands |  |  | 9 Months Ended
--- | --- | --- | ---
Mar. 09, 2020 USD ($) property | Jan. 27, 2020 USD ($) property | Sep. 30, 2020 USD ($) property mortgage | Sep. 30, 2019 USD ($) property
Debt Instrument [Line Items] |  |  |  |
Debt repaid | $ |  |  | $ 31,667 | $ 48,116
Number of properties collateralized in mortgage notes payable |  |  | 120 |
Weighted average interest rate on fixed rate debt (as percent) |  |  | 4.28% |
Number of properties acquired |  |  | 6 | 9
Fixed rate mortgage loans |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Number of long term mortgages repaid | mortgage |  |  | 4 |
Number of properties | mortgage |  |  | 5 |
Debt repaid | $ |  |  | $ 5,918 |
Stated interest rate (as percent) |  |  | 6.00% |
Number of properties collateralized in mortgage notes payable |  |  | 61 |
New Fixed rate mortgage loans |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Number of mortgage notes payable | mortgage |  |  | 4 |
Number of properties collateralized in mortgage notes payable |  |  | 4 |
Variable rate mortgage loans |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt repaid | $ |  |  | $ 16,107 |
Number of properties collateralized in mortgage notes payable |  |  | 8 |
New fixed rate mortgage notes payable |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Aggregate fixed rate debt issued | $ |  |  | $ 35,855 |
Weighted average interest rate on fixed rate debt (as percent) |  |  | 3.22% |
New fixed rate mortgage notes payable | Property maturing February 1, 2030 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate (as percent) |  | 3.625% |  |
Aggregate fixed rate debt issued | $ |  | $ 18,300 |  |
Number of properties acquired |  | 3 |  |
New fixed rate mortgage notes payable | Property maturing June 18, 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate (as percent) | 2.80% |  |  |
Aggregate fixed rate debt issued | $ | $ 17,500 |  |  |
Number of properties acquired | 1 |  |  |
LIBOR | Variable rate mortgage loans |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average interest rate variable rate debt repaid (as percent) |  |  | 2.19% |

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