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v3.21.2

Subsequent Events (Details) $ in Thousands |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Oct. 15, 2021 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Oct. 29, 2021 ft² | Oct. 25, 2021 USD ($) ft² Buildings | Oct. 19, 2021 ft²
Subsequent Event [Line Items] |  |  |  |  |  |
Repayments of Unsecured Debt |  | $ 843,710 | $ 0 |  |  |
Boston Properties Limited Partnership |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Repayments of Unsecured Debt |  | $ 843,710 | $ 0 |  |  |
Subsequent Event [Member] | 3.954% unsecured senior notes | Boston Properties Limited Partnership |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Debt Instrument, Face Amount | $ 1,000,000 |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.85% |  |  |  |  |
Repayments of Unsecured Debt | $ 1,050,000 |  |  |  |  |
Redemption Premium | 43,900 |  |  |  |  |
Debt Instrument, Increase, Accrued Interest | $ 7,900 |  |  |  |  |
Subsequent Event [Member] | 181, 191 and 201 Spring Street |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Contractual Sales Price |  |  |  |  | $ 191,500 |
Net Rentable Area (in sf) | ft² |  |  |  |  | 333,000 |
Leased percentage |  |  |  |  | 100.00% |
Number of real estate properties | Buildings |  |  |  |  | 3 |
Subsequent Event [Member] | 7750 Wisconsin Avenue [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  | 734,000 |  |
Ownership Percentage |  |  |  | 50.00% |  |
Subsequent Event [Member] | Reston Next |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  | 1,100,000

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