General And Limited Partners Capital Account

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- Definition

Number of VIEs - consolidated

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- Definition

Number of VIEs - Total

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No definition available.

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- Definition

Summary Of Significant Accounting Policies [Line Items]

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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- Definition

Amount of realized and unrealized gain (loss) on investment.

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- Definition

Amount of interest capitalized during the period.

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- Definition

Carrying amount of the equity interests owned by noncontrolling partners in an operating partnership included in the entity's consolidated financial statements.

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No definition available.

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- Definition

As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of preferred shares (regardless of class), preferred partnership units (regardless of class), preferential membership interests, or any other form of preferred equity regardless of investee entity legal form.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Summary Of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 18, 2021 $ / shares	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Interest capitalized	$ 12,032	$ 14,149
Gains (losses) from investments in securities	1,659	(5,445)
Adoption of ASU 2016-13 and 2018-19	(570,982)			$ (509,653)
Adoption of ASU 2016-13 and 2018-19	$ 620,106			616,596
Number of VIEs - Total	7
Number of VIEs	6
Distributions Payable, Amount Per Unit \| $ / shares			$ 0.98
Boston Properties Limited Partnership
Summary Of Significant Accounting Policies [Line Items]
Interest capitalized	$ 12,032	14,149
Gains (losses) from investments in securities	1,659	$ (5,445)
Adoption of ASU 2016-13 and 2018-19	4,392,624			4,554,639
Adoption of ASU 2016-13 and 2018-19	$ 1,780,044			$ 1,643,024
Distributions Payable, Amount Per Unit \| $ / shares			$ 0.98
Commercial Real Estate Properties [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of VIEs	5