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- Definition

Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

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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

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

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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=98514028&loc=d3e3179-108585

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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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Real Estate Narrative (Details) $ in Thousands					2 Months Ended	3 Months Ended		5 Months Ended	6 Months Ended
Real Estate Narrative (Details) $ in Thousands	May 24, 2018 USD ($) ft²	Feb. 23, 2018 ft²	Jan. 09, 2018 USD ($) ft²	Jan. 08, 2018 USD ($)	May 23, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	May 23, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 20, 2018 ft² apartments	Jun. 07, 2018 ft² apartments	Jan. 24, 2018 ft²
Real Estate [Line Items]
Proceeds from sales of real estate									$ 141,249	$ 17,049
Gains on sales of real estate						$ 18,292	$ 3,767		114,689	3,900
17Fifty Presidents Street [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²													276,000
Signature at Reston [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²												518,000
Number of apartment units \| apartments												508
Reston Gateway [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²		1,100,000.0
Square Footage Of Signed Lease \| ft²		850,000
Proto Kendall Square [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²											167,000
Number of apartment units \| apartments											280
Boston Properties Limited Partnership
Real Estate [Line Items]
Proceeds from sales of real estate									141,249	17,049
Gains on sales of real estate						$ 18,770	4,344		$ 117,677	4,477
500 E Street [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²			262,000
Net Contractual Sales Price			$ 118,600
Net income (loss)				$ 100			1,600			3,200
Proceeds from sales of real estate			116,100
Gains on sales of real estate			96,400
500 E Street [Member] \| Boston Properties Limited Partnership
Real Estate [Line Items]
Gains on sales of real estate			$ 98,900
91 Hartwell Avenue [Member]
Real Estate [Line Items]
Net Rentable Area (in sf) \| ft²	119,000
Gross Sale Price	$ 22,200
Net income (loss)					$ 100		$ 100	$ 300		$ 300
Proceeds from sales of real estate	21,700
Gains on sales of real estate	15,500
91 Hartwell Avenue [Member] \| Boston Properties Limited Partnership
Real Estate [Line Items]
Gains on sales of real estate	$ 15,900