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v3.25.4

Exchangeable Senior Notes (Details) |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 29, 2025 USD ($) $ / shares $ / Unit | Dec. 31, 2025 USD ($) $ / shares | Dec. 31, 2025 USD ($) $ / shares | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 24, 2025 $ / shares
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Conversion, Converted Instrument, Amount |  |  | $ 0 | $ 100,000,000 | $ 0 |
Closing price of common stock (in dollars per share) | $ / shares |  | $ 67.48 | $ 67.48 |  |  |
Capped call transactions premium |  |  | $ 35,000,000 | 0 | 0 |
Boston Properties Limited Partnership |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt |  | $ 9,850,000,000 | 9,850,000,000 |  |  |
Debt Conversion, Converted Instrument, Amount |  |  | 0 | 100,000,000 | 0 |
Capped call transactions premium |  |  | 35,000,000 | $ 0 | $ 0 |
2.00% unsecured exchangeable senior notes | Convertible Debt |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt | $ 1,000,000,000.0 |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 2.00% |  |  |  |  |
Debt Instrument, Maturity Date | Oct. 01, 2030 |  |  |  |  |
Proceeds From Convertible Debt, Net of Issuance and Hedging Costs | $ 975,100,000 |  |  |  |  |
Interest Expense, Nonoperating |  | 5,100,000 |  |  |  |
Amortization of Debt Issuance Costs |  | 1,300,000 |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 2.498% |  |  |  |  |
Unamortized Debt Issuance Expense |  | $ 23,700,000 | $ 23,700,000 |  |  |
Debt Instrument, Convertible, Earliest Date | Jul. 01, 2030 |  |  |  |  |
Debt Conversion, Converted Instrument, Amount | $ 1,000 |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares | $ 92.44 |  |  |  |  |
Debt Instrument, Convertible, Exchange Premium Percentage | 22.50% |  |  |  |  |
Closing price of common stock (in dollars per share) | $ / shares |  |  |  |  |  | $ 75.46
Debt Instrument, Redemption Price, Percentage | 130.00% |  |  |  |  |
2.00% unsecured exchangeable senior notes | Convertible Debt | Call Option |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Derivative, Cap Price | $ / Unit | 105.64 |  |  |  |  |
Capped call transactions premium | $ 35,000,000.0 |  |  |  |  |
2.00% unsecured exchangeable senior notes | Convertible Debt | Per $1,000 principal amount |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Ratio | 10.8180 |  |  |  |  |
2.00% unsecured exchangeable senior notes | Convertible Debt | Boston Properties Limited Partnership |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt | $ 1,000,000,000.0 |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 2.00% |  |  |  |  |

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