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v3.25.3

Notes Payable, Bank Credit Facility, Interest and Amortization of Deferred Debt Costs - Narrative (Details) | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Oct. 01, 2030 | Oct. 01, 2027 | Aug. 20, 2025 USD ($) | Aug. 23, 2022 USD ($) swap
Debt Instrument [Line Items] |  |  |  |  |  |
Principal amount | $ 1,611,969,000 | $ 1,600,000,000 |  |  |  |
Notes payable, principal balance | 1,380,000,000 |  |  |  |  |
Debt outstanding with variable-rate | 230,000,000 | 187,000,000.0 |  |  |  |
Carrying value of properties collateralizing mortgage notes | 1,600,000,000 | 1,600,000,000 |  |  |  |
Debt outstanding with fixed-rate |  | 1,370,000,000 |  |  |  |
Revolving credit facility payable, net | 185,376,000 | 186,489,000 |  |  |  |
Number of interest rate swaps | swap |  |  |  |  |  | 2
Long-term debt | 1,588,059,000 |  |  |  |  |
Unamortized deferred debt costs | 23,910,000 | 20,100,000 |  |  |  |
Debt issuance costs amortization | 9,700,000 | $ 11,200,000 |  |  |  |
Thruway Mortgage |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Principal amount | 68,900,000 |  |  |  |  |
Long-term debt | $ 17,500,000 |  |  |  |  |
Twinbrook Quarter |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Guarantor obligations, liquidation proceeds, percentage (as percent) | 100.00% |  |  |  |  |
Twinbrook Quarter |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, remaining borrowing capacity | $ 6,100,000 |  |  |  |  |
Long-term debt | 138,900,000 |  |  |  |  |
Hampden House |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, remaining borrowing capacity | $ 25,400,000 |  |  |  |  |
Guarantor obligations, liquidation proceeds, percentage (as percent) | 100.00% |  |  |  |  |
Guarantor obligations, current carrying value | $ 26,600,000 |  |  |  |  |
Guarantor obligations, maximum exposure | $ 107,600,000 |  |  |  |  |
Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate spread (as percent) | 1.40% | 1.40% |  |  |  |
Term Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate spread (as percent) | 1.35% | 1.35% |  |  |  |
Unsecured Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, remaining borrowing capacity | $ 101,100,000 | $ 134,500,000 |  |  |  |
Revolving credit facility payable, net | 330,000,000 | 287,000,000.0 |  |  |  |
Letter of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Revolving credit facility payable, net | 185,000 | 185,000 |  |  |  |
Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 600,000,000 | 525,000,000 |  |  |  |
Line of Credit | Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 190,000,000.0 |  |  |  |  |
Line of Credit | Term Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 140,000,000 | 100,000,000.0 |  |  |  |
Line of Credit | New Revolving Credit Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 460,000,000 | $ 425,000,000 |  |  |  |
Secured Debt | Term Loan |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  |  | $ 100,000,000.0
Secured Debt | Term Loan | Agreement Ending October 1, 2030 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Derivative, notional amount |  |  |  |  |  | 50,000,000.0
Secured Debt | Term Loan | Agreement Ending October 1, 2030 | Forecast |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Derivative, fixed interest rate (as a percent) |  |  | 2.91% |  |  |
Secured Debt | Term Loan | Agreement Ending October 1, 2027 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Derivative, notional amount |  |  |  |  |  | $ 50,000,000.0
Secured Debt | Term Loan | Agreement Ending October 1, 2027 | Forecast |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Derivative, fixed interest rate (as a percent) |  |  |  | 2.96% |  |
Mortgages | Kentlands Place Mortgage |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt |  |  |  |  | $ 25,900,000 |

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