Earned wards - Target

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- Definition

Final awards percentage of target

+ References

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- Definition

Maximum Earned Awards

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- Definition

Minimum earned awards

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- Definition

Value of MYLTIP Awards

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Net rentable area for properties owned.

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- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Number of shares issued under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details) $ in Millions			12 Months Ended
Subsequent Events (Details) $ in Millions	Feb. 04, 2022 USD ($) shares	Feb. 01, 2022 USD ($) shares	Dec. 31, 2021 shares	Dec. 31, 2020 shares	Dec. 31, 2019 shares	Feb. 02, 2022 ft²	Jan. 28, 2022 shares	Jan. 18, 2022 ft²
Subsequent Event [Line Items]
Common stock, shares issued			156,623,749	155,797,725
Restricted Stock [Member]
Subsequent Event [Line Items]
Common stock, shares issued			57,383	29,630	26,503
Boston Properties Limited Partnership \| LTIP Units [Member]
Subsequent Event [Line Items]
Number of shares issued			281,640	207,181	181,919
Boston Properties Limited Partnership \| MYLTIP 2019 [Member]
Subsequent Event [Line Items]
Number of shares issued					220,734
Subsequent Event [Member] \| 651 Gateway
Subsequent Event [Line Items]
Ownership Percentage								50.00%
Subsequent Event [Member] \| 651 Gateway \| Construction
Subsequent Event [Line Items]
Net Rentable Area (in sf) \| ft²								293,000
Subsequent Event [Member] \| Platform 16
Subsequent Event [Line Items]
Ownership Percentage						55.00%
Subsequent Event [Member] \| Platform 16 \| Scenario, Plan
Subsequent Event [Line Items]
Net Rentable Area (in sf) \| ft²						1,100,000
Subsequent Event [Member] \| Platform 16 \| Construction
Subsequent Event [Line Items]
Net Rentable Area (in sf) \| ft²						390,000
Subsequent Event [Member] \| Restricted Stock [Member]
Subsequent Event [Line Items]
Common stock, shares issued							33,091
Subsequent Event [Member] \| MYLTIP 2022
Subsequent Event [Line Items]
Minimum earned awards		0
Maximum Earned Awards		254,061
Earned awards - Target		127,031
Value of MYLTIP Awards \| $		$ 17.3
Subsequent Event [Member] \| MYLTIP 2019 [Member]
Subsequent Event [Line Items]
Value of MYLTIP Awards \| $	$ 8.6
Final awards percentage of target	69.00%
Forfeitures, in units	144,043
Subsequent Event [Member] \| Boston Properties Limited Partnership \| LTIP Units [Member]
Subsequent Event [Line Items]
Number of shares issued		249,873