Portion of Building Leased (percentage)

No definition available.

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- Definition

Sale Price Of Sold Property

+ References

No definition available.

+ Details

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- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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- Definition

This element represents the amount of gain (loss) on sale of properties during the reporting period gross of the applicable income taxes realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 974
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-15.(a)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6875705&loc=d3e641549-123027

+ Details

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

+ Details

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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.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Details

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Real Estate Activity During the Six Months Ended June 30, 2016 (Narrative) (Details)			1 Months Ended	2 Months Ended	3 Months Ended		6 Months Ended
	Feb. 03, 2016 USD ($) ft²	Feb. 01, 2016 USD ($) ft²	Jan. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 24, 2016 ft²	May 27, 2016 ft²	Apr. 22, 2016 USD ($) ft²
Real Estate Properties [Line Items]
Net income (loss)					$ 218,124,000	$ 204,926,000	$ 468,477,000	$ 411,135,000
Proceeds from sales of real estate							104,816,000	194,821,000
Gains on sales of real estate					0	0	67,623,000	95,084,000
Revenues					623,546,000	618,221,000	1,289,531,000	1,236,697,000
415 Main Street [Member]
Real Estate Properties [Line Items]
Net income (loss)			$ 1,200,000			3,700,000		6,300,000
Sale Price Of Sold Property		$ 105,400,000
Proceeds from sales of real estate		$ 104,900,000
Net Rentable Area (in sf) \| ft²		231,000
601 Massachusetts Avenue [Member]
Real Estate Properties [Line Items]
Net Rentable Area (in sf) \| ft²										479,000
804 Carnegie Center [Member]
Real Estate Properties [Line Items]
Net Rentable Area (in sf) \| ft²										130,000
10 CityPoint [Member]
Real Estate Properties [Line Items]
Net Rentable Area (in sf) \| ft²									241,000
Terminated lease at 250 West 55thStreet in NYC [Member]
Real Estate Properties [Line Items]
Net Rentable Area (in sf) \| ft²	85,000
Revenues	$ 45,000,000
Boston Properties Inc \| 415 Main Street [Member]
Real Estate Properties [Line Items]
Gains on sales of real estate		$ 60,800,000
Boston Properties Limited Partnership
Real Estate Properties [Line Items]
Net income (loss)					220,108,000	206,924,000	472,448,000	415,132,000
Proceeds from sales of real estate							104,816,000	194,821,000
Gains on sales of real estate					0	0	69,792,000	95,084,000
Revenues					$ 623,546,000	$ 618,221,000	$ 1,289,531,000	$ 1,236,697,000
Boston Properties Limited Partnership \| 415 Main Street [Member]
Real Estate Properties [Line Items]
Gains on sales of real estate		$ 63,000,000
Peterson Way [Member]
Real Estate Properties [Line Items]
Purchase price											$ 78,000,000
Net income (loss)				$ (94,000)
Net Rentable Area (in sf) \| ft²											218,000
Portion of Building Leased (percentage)											100.00%
Revenues				$ 1,100,000
Future development [Member] \| Peterson Way [Member]
Real Estate Properties [Line Items]
Net Rentable Area (in sf) \| ft²											632,000