v3.20.2

Unsecured Credit Agreements - Summary of Unsecured Credit Agreements (Parenthetical) (Detail) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
2020 Unsecured Term Loan |  |
Debt Instrument [Line Items] |  |
Maturity date | Aug. 31, 2020 |
Debt instrument extension options, description | two six-month extensions |
Maturity extension fee on outstanding principal balance percentage | 0.05% |
Debt instrument maturity date extension | Feb. 02, 2021 |
Unsecured Debt | 2020 Unsecured Term Loan |  |
Debt Instrument [Line Items] |  |
Maturity date | Feb. 28, 2021 |
Unsecured Debt | 1 Month LIBOR |  |
Debt Instrument [Line Items] |  |
Interest rate | 0.16% | 1.76%

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