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

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

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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- Definition

High end of the range of fixed interest rates when a range is presented for a group of interest rate derivatives.

+ References

No definition available.

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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

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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Low end of the range of fixed interest rates when a range is presented for a group of interest rate derivatives.

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- Definition

Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Derivative and Hedging Instruments Derivative Instrument and Hedging Activities Notional Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jan. 06, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value	$ (47,144)	$ (10,302)	$ 0
Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		950,000
Fair Value		(10,302)
Boston Properties Limited Partnership \| Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		550,000
Fair Value		(4,231)
Boston Properties Limited Partnership \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.129% - 2.325% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Notional Amount		$ 150,000
Derivative, Lower Fixed Interest Rate Range		2.129%
Derivative, Higher Fixed Interest Rate Range		2.325%
Fair Value		$ 1,188
Boston Properties Limited Partnership \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.348% - 2.571% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Notional Amount		$ 400,000
Derivative, Lower Fixed Interest Rate Range		2.348%
Derivative, Higher Fixed Interest Rate Range		2.571%
Fair Value		$ (5,419)
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	450,000	400,000		$ 50,000
Fair Value	(8,264)	(6,071)
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.336% - 2.430% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Notional Amount		$ 150,000
Derivative, Lower Fixed Interest Rate Range		2.336%
Derivative, Higher Fixed Interest Rate Range		2.43%
Fair Value		$ 1,176
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.677% - 2.950% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Notional Amount		$ 250,000
Derivative, Lower Fixed Interest Rate Range		2.677%
Derivative, Higher Fixed Interest Rate Range		2.95%
Fair Value		$ (7,247)
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.418% - 2.950% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Notional Amount	$ 350,000
Derivative, Lower Fixed Interest Rate Range	2.418%
Derivative, Higher Fixed Interest Rate Range	2.95%
Fair Value	$ (8,773)
767 Fifth Partners LLC [Member] \| Interest Rate Swap [Member] \| Interest Rate Swap Range 2.366% to 2.388% [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Notional Amount	$ 100,000
Derivative, Lower Fixed Interest Rate Range	2.336%
Derivative, Higher Fixed Interest Rate Range	2.388%
Fair Value	$ 509