Derivative Instruments and Hedging Activities (Details) $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($) swaps yr	Dec. 31, 2015 USD ($)
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative, Net Liability Position, Aggregate Fair Value	$ 101,600
Assets Needed for Immediate Settlement, Aggregate Fair Value	101,600
Amount of loss related to the effective portion recognized in accumulated other comprehensive loss	101,300
Notional Amount	1,000,000	$ 950,000
Estimated current balance held in Accumulated Other Comprehensive Loss to be reclassified into earnings within the next twelve months	$ (4,800)
Boston Properties Limited Partnership \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Number of interest rate swap agreements entered into (swap contracts) \| swaps	17
Term of anticipated mortgage loan (in years) \| yr	10
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) \| yr	10
Average Fixed Interest Rate	2.423%
Notional Amount	$ 550,000	550,000
767 Fifth Partners LLC [Member]
Debt Instrument [Line Items]
Ownership Percentage by the Company	60.00%
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Number of interest rate swap agreements entered into (swap contracts) \| swaps	16
Term of anticipated mortgage loan (in years) \| yr	10
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) \| yr	10
Average Fixed Interest Rate	2.619%
Notional Amount	$ 450,000	$ 400,000

Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years)

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- Definition

Number of interest rate swap agreements entered into

+ References

No definition available.

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- Definition

Term of anticipated mortgage loan (in years)

+ References

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624258-113959

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

The effective portion of losses on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624258-113959

+ Details

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Balance Type:	credit
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Details

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