Aggregate purchase price

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- Definition

Contractual Sales Price

+ References

No definition available.

+ Details

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- Definition

Ground Lease Term (in years)

+ References

No definition available.

+ Details

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- Definition

Number of apartment units

+ References

No definition available.

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- Definition

Square Footage Of Signed Lease.

+ References

No definition available.

+ Details

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- Definition

Term of Lease Signed (in years)

+ References

No definition available.

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- Definition

Area of land held.

+ References

No definition available.

+ Details

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- Definition

Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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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

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

+ References

No definition available.

+ Details

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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Balance Type:	na
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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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Balance Type:	credit
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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=66902209&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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- 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=63488584&loc=d3e20235-122688

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- Details

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Real Estate (Narrative) (Details)					3 Months Ended								5 Months Ended	8 Months Ended	12 Months Ended
Real Estate (Narrative) (Details)	Dec. 01, 2017 ft² yr	Aug. 30, 2017 USD ($) a	Jun. 13, 2017 USD ($) ft²	Apr. 19, 2017 USD ($) a	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Jun. 13, 2017 USD ($) ft²	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Nov. 28, 2017 ft²	Nov. 17, 2017 ft²	Sep. 16, 2017 ft²	Aug. 24, 2017 ft² yr	Jun. 29, 2017 USD ($) yr apartments	May 27, 2017 ft²	May 15, 2017 USD ($) ft²	Apr. 06, 2017 ft²
Real Estate Properties [Line Items]
Revenues					$ 655,229,000	$ 657,712,000	$ 656,907,000	$ 632,228,000	$ 636,061,000	$ 625,228,000	$ 623,546,000	$ 665,985,000			$ 2,602,076,000	$ 2,550,820,000	$ 2,490,821,000
Operating Income (Loss)															908,110,000	825,784,000	849,365,000
Proceeds from sales of real estate															29,810,000	122,750,000	602,600,000
Gains on sales of real estate															7,663,000	80,606,000	375,895,000
Present value of expected net minimum lease payments					51,596,000									$ 51,596,000	51,596,000
30 Shattuck Road [Member]
Real Estate Properties [Line Items]
Contractual Sales Price				$ 5,000,000
Proceeds from sales of real estate				5,000,000
Gains on sales of real estate				$ 3,700,000
Area of Land \| a				9.5
40 Shattuck Road [Member]
Real Estate Properties [Line Items]
Net Rentable Area \| ft²			122,000										122,000
Operating Income (Loss)													$ (28,000)			(50,000)	300,000
Contractual Sales Price			$ 12,000,000										$ 12,000,000
Proceeds from sales of real estate			11,900,000
Gains on sales of real estate			28,000
Reston Eastgate [Member]
Real Estate Properties [Line Items]
Contractual Sales Price		$ 14,000,000
Proceeds from sales of real estate		13,200,000
Gains on sales of real estate		$ 2,800,000
Area of Land \| a		21.7
145 Broadway
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																									485,000
Reservoir Place North [Member]
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																							73,000
103 Carnegie Center [Member] \| 103 Carnegie Center [Member]
Real Estate Properties [Line Items]
Aggregate purchase price																								$ 15,800,000
Net Rentable Area \| ft²																								96,000
Revenues														1,700,000
Operating Income (Loss)														$ (300,000)
6595 Springfield Center Drive (TSA Headquarters)
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																					634,000
Term of Lease Signed (in years) \| yr																					15
888 Boylston Street [Member]
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																				417,000
191 Spring Street
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																			171,000
20 CityPoint
Real Estate Properties [Line Items]
Net Rentable Area \| ft²																		211,000
2100 Pennsylvania Avenue [Member]
Real Estate Properties [Line Items]
Net Rentable Area \| ft²	469,000
Ground Lease Term (in years) \| yr	75
Term of Lease Signed (in years) \| yr	16
Square Footage Of Signed Lease \| ft²	288,000
MacArthur Transit Center [Member]
Real Estate Properties [Line Items]
Term of Lease Signed (in years) \| yr																						99
Number of apartment units \| apartments																						402
Present value of expected net minimum lease payments																						$ 28,962,000
Boston Properties Limited Partnership
Real Estate Properties [Line Items]
Revenues					$ 655,229,000	$ 657,712,000	$ 656,907,000	$ 632,228,000	$ 636,061,000	$ 625,228,000	$ 623,546,000	$ 665,985,000			2,602,076,000	2,550,820,000	2,490,821,000
Operating Income (Loss)															916,250,000	837,411,000	857,358,000
Proceeds from sales of real estate															29,810,000	122,750,000	602,600,000
Gains on sales of real estate															$ 8,240,000	$ 82,775,000	$ 377,093,000
Boston Properties Limited Partnership \| 40 Shattuck Road [Member]
Real Estate Properties [Line Items]
Gains on sales of real estate			$ 600,000
Consolidated Properties [Member] \| Salesforce Tower [Member]
Real Estate Properties [Line Items]
Net Rentable Area \| ft²	1,400,000
Ownership Percentage by Parent	95.00%