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Stockholders' Equity / Partners' Capital Narrative (Details) |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 02, 2017 USD ($) yr | Sep. 30, 2019 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares | Mar. 27, 2018 $ / shares | Jun. 03, 2014 USD ($)
Class of Stock [Line Items] |  |  |  |  |
Common stock, shares outstanding |  | 154,572,073 | 154,458,478 |  |
General Partners' Capital Account, Units Outstanding |  | 1,725,828 |  |  |
Limited Partners' Capital Account, Units Outstanding |  | 152,846,245 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period |  | 29,704 |  |  |
Shares of Common Stock in connection with the redemption of an equal number of OP Units (in shares) |  | 41,577 |  |  |
Common Stock, Value, Issued | $ |  | $ 1,546,000 | $ 1,545,000 |  |
ATM Program [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
At the market stock offering program, aggregate value of common stock | $ | $ 600,000,000.0 |  |  |  | $ 600,000,000.0
At Market Stock Offering Program Maximum Length Of Sale In Years | yr | 3 |  |  |  |
Common Stock, Value, Issued | $ |  | $ 0 |  |  |
Series B Cumulative Redeemable Preferred Stock [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 |  | $ 2,500.00 | $ 2,500 | $ 2,500.00 |
Ratio of depository shares to shares of Series B Preferred Stock |  | 0.01 |  |  |
Depository shares of Series B Cumulative Redeemable Preferred [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 8,000,000 |  |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 25.00 |  | $ 25.00 |
Boston Properties Limited Partnership |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
General Partners' Capital Account, Units Outstanding |  | 1,725,828 | 1,722,336 |  |
Limited Partners' Capital Account, Units Outstanding |  | 152,846,245 | 152,736,142 |  |
Boston Properties Limited Partnership | Series B Cumulative Redeemable Preferred Stock [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 80,000 | 80,000 |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 2,500 | $ 2,500 |  |

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