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Stockholders' Equity / Partners' Capital Narrative (Details) $ / shares in Units, $ in Thousands |  |  |  |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 01, 2021 shares | Mar. 31, 2021 USD ($) | Mar. 02, 2021 $ / shares shares | May 22, 2020 USD ($) yr | Sep. 30, 2021 USD ($) shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) shares | Sep. 30, 2020 USD ($) | Dec. 31, 2020 $ / shares shares | Jun. 02, 2017 USD ($)
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Outstanding |  |  |  |  | 156,206,491 |  | 156,206,491 |  | 155,718,825 |
General Partners' Capital Account, Units Outstanding (in units) |  |  |  |  | 1,736,833 |  | 1,736,833 |  |  |
Limited Partners' Capital Account, Units Outstanding (in units) |  |  |  |  | 154,469,658 |  | 154,469,658 |  |  |
Options exercised |  |  |  |  |  |  | 206,377 |  |  |
Shares of Common Stock issued in connection with redemption of an equal number of OP Units (in shares) |  |  |  |  |  |  | 227,233 |  |  |
Preferred Stock Redemption Premium | $ |  |  |  |  | $ 0 | $ 0 | $ 6,412 | $ 0 |  |
ATM Program [Member] |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
At The Market Stock Offering Program Aggregate Value Of Common Stock | $ |  |  |  | $ 600,000 |  |  |  |  |  | $ 600,000
At Market Stock Offering Program Maximum Length Of Sale (in years) | yr |  |  |  | 3 |  |  |  |  |  |
Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Series B, Shares Outstanding (in shares) |  |  | 80,000 |  |  |  |  |  | 80,000 |
Series B, Dividend Rate, Percentage |  |  | 5.25% |  |  |  |  |  |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 2,500 |
Preferred Stock, Redemption Price Per Share | $ / shares |  |  | $ 2,500 |  |  |  |  |  |  |
Preferred Stock Redemption Price Per Share, plus accrued and unpaid dividends | $ / shares |  |  | $ 2,516.41 |  |  |  |  |  |  |
Preferred Stock, Redemption Amount | $ |  | $ (201,300) |  |  |  |  |  |  |  |
Redeemable Preferred Stock Dividends | $ |  | $ 1,300 |  |  |  |  |  |  |  |
Preferred Stock Redemption Premium | $ |  |  |  |  |  |  | $ 6,400 |  |  |
Preferred Stock, Redemption Date | Apr. 01, 2021 |  |  |  |  |  |  |  |  |
OP Units for redemption (in shares) | 80,000 |  |  |  |  |  |  |  |  |
Depositary shares of Series B Cumulative Redeemable Preferred [Member] |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Series B, Shares Outstanding (in shares) |  |  |  |  |  |  |  |  | 8,000,000 |
OP Units for redemption (in shares) | 8,000,000 |  |  |  |  |  |  |  |  |
Boston Properties Limited Partnership | Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Series B, Shares Outstanding (in shares) |  |  |  |  |  |  |  |  | 80,000 |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 2,500 |

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