v3.21.2

Unsecured Credit Agreements - Summary of Unsecured Credit Agreements (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020 | Sep. 15, 2021
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate | 5.00% |  |
Total unsecured debt | $ 1,597,868 | $ 1,547,667 |
Debt issuance costs, net | (4,658) | (6,435) |
Long-term Debt | 1,597,868 |  |
2031 Senior Unsecured Public Notes |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate |  |  | 2.60%
Total unsecured debt |  |  | $ 375,000
Unsecured Debt |  |  |
Debt Instrument [Line Items] |  |  |
Long-term Debt | 1,490,123 | 1,433,796 |
Unsecured Debt | Term Loan [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Total unsecured debt | 650,000 | 965,000 |
Debt issuance costs, net | (3,542) | (3,670) |
Long-term Debt | 646,458 | 961,330 |
Unsecured Debt | Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Total unsecured debt | 850,000 | 475,000 |
Unamortized debt issuance costs and original issuance discount, net | 6,335 | 2,534 |
Long-term Debt | $ 843,665 | 472,466 |
Unsecured Debt | Unsecured Revolving Credit Facility |  |  |
Debt Instrument [Line Items] |  |  |
Maturity Date | 2023-09 |  |
Total unsecured debt | $ 0 | 0 |
Unsecured Debt | 2022 Unsecured Term Loan |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | one-month LIBOR + 1.00% |  |
Maturity Date | 2022-02 |  |
Total unsecured debt | $ 60,000 | $ 60,000 |
Unsecured Debt | 2022 Unsecured Term Loan | 1 Month LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Basis spread on variable rate | 1.00% | 1.25% |
Unsecured Debt | 2023 Unsecured Term Loan |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | one-month LIBOR + 1.10% |  |
Maturity Date | 2023-01 |  |
Total unsecured debt | $ 0 | $ 265,000 |
Unsecured Debt | 2023 Unsecured Term Loan | 1 Month LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Basis spread on variable rate | 1.10% | 1.35% |
Unsecured Debt | 2024 Unsecured Term Loan |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | one-month LIBOR + 1.00% |  |
Maturity Date | 2024-06 |  |
Total unsecured debt | $ 190,000 | $ 190,000 |
Unsecured Debt | 2024 Unsecured Term Loan | 1 Month LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Basis spread on variable rate | 1.00% | 1.25% |
Unsecured Debt | 2026 Unsecured Term Loan |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | one-month LIBOR + 1.00% |  |
Maturity Date | 2026-02 |  |
Total unsecured debt | $ 400,000 | $ 450,000 |
Unsecured Debt | 2026 Unsecured Term Loan | 1 Month LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Basis spread on variable rate | 1.00% | 1.85% |
Unsecured Debt | 2027 Senior Unsecured Notes | Senior Guaranteed Notes Series A |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate | 4.84% |  |
Maturity Date | 2027-04 |  |
Total unsecured debt | $ 150,000 | $ 150,000 |
Unsecured Debt | 2028 Senior Unsecured Notes | Senior Guaranteed Notes Series B |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate | 5.09% |  |
Maturity Date | 2028-07 |  |
Total unsecured debt | $ 225,000 | 225,000 |
Unsecured Debt | 2030 Senior Unsecured Notes | Senior Guaranteed Notes Series C |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate | 5.19% |  |
Maturity Date | 2030-07 |  |
Total unsecured debt | $ 100,000 | 100,000 |
Unsecured Debt | 2031 Senior Unsecured Public Notes | Senior Notes |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, interest rate | 2.60% |  |
Maturity Date | 2031-09 |  |
Total unsecured debt | $ 375,000 |  |

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