2013 MYLTIP

No definition available.

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- Definition

Accelerated Compensation Expenses Related To 2011 Opp Units

+ References

No definition available.

+ Details

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- Definition

Common Stock Marketable Quoted Value Per Share

+ References

No definition available.

+ Details

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- Definition

Common Units Of Operating Partnership If Converted Value

+ References

No definition available.

+ Details

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- Definition

Distributions Declared To OP And LTIP Units Per Unit

+ References

No definition available.

+ Details

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- Definition

Distributions Declared To OPP and MYLTIP Units Per Unit

+ References

No definition available.

+ Details

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- Definition

Distributions Made To OP And LTIP Units Per Unit

+ References

No definition available.

+ Details

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- Definition

Distributions Made To OPP and MYLTIP Units Per Unit

+ References

No definition available.

+ Details

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- Definition

One OP Unit is equivalent to one common stock (share).

+ References

No definition available.

+ Details

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- Definition

OP Units redeemed for stock from LTIP Units

+ References

No definition available.

+ Details

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- Definition

Outperformance Awards Long Term Incentive Plan Units

+ References

No definition available.

+ Details

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- Definition

Prior to the measurement date on February 5, 2011, 2008 OPP Units will be entitled to receive per unit distributions equal to one-tenth (10%) of the regular quarterly distributions payable on an OP Unit, but will not be entitled to receive any special distributions.

+ References

No definition available.

+ Details

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- Definition

Redemption Of OP Units Issued On Conversion Of LTIP Units

+ References

No definition available.

+ Details

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- Definition

Restriction on redemption of OP unit to Common Stock

+ References

No definition available.

+ Details

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- Definition

2014 MYLTIP

+ References

No definition available.

+ Details

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- Details

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- Definition

Date of record for distribution of cash or unit to limited partner of limited partnership (LP), in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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(Common Units) (Narrative) (Details) (USD $)	0 Months Ended			9 Months Ended
(Common Units) (Narrative) (Details) (USD $)	Jul. 31, 2014	Apr. 30, 2014	Jan. 29, 2014	Sep. 30, 2014 Y	Sep. 11, 2014
OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
OP Units for redemption (in shares)				70,422
Redemption of OP units issued on conversion of LTIP Units (in shares)				67,368
Outperformance Awards LTIP Units distribution as percentage of OP Unit distribution prior to measurement date				10.00%
Distributions made to OP and LTIP units per unit (in dollars per share)	$ 0.65	$ 0.65	$ 0.65
Distribution paid to outperformance awards, OPP Units and MYLTIP Units (in dollars per share)	$ 0.065	$ 0.065	$ 0.065
Distribution declared to OP and LTIP units by Boston Properties, Inc. (in dollars per share)					$ 0.65
Distribution declared to outperformance awards OPP Units by Boston Properties, Inc. (in dollars per share)					$ 0.065
Restriction on redemption of OP Unit to Common Stock (in years)				1
Redemption of OP Unit equivalence to Common Stock (in shares)				1
Common units of operating partnership if converted value				$ 2,100,000,000
Closing price of common stock (in dollars per share)				$ 115.76
OPP Units 2012 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Outperformance awards in LTIP Units (in shares)				394,590
MYLTIP [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
2013 MYLTIP				314,974
MYLTIP 2014 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
2014 MYLTIP				483,555
Quarter 4 2013 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Jan. 29, 2014
Quarter 4 2013 [Member] \| OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Jan. 29, 2014
Holders of record date				Dec. 31, 2013
Quarter 1 2014 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Apr. 30, 2014
Quarter 1 2014 [Member] \| OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Apr. 30, 2014
Holders of record date				Mar. 31, 2014
Quarter 2 2014 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Jul. 31, 2014
Quarter 2 2014 [Member] \| OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Jul. 31, 2014
Holders of record date				Jun. 30, 2014
Quarter 3 2014 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Oct. 31, 2014
Dividends payable, date declared				Sep. 11, 2014
Quarter 3 2014 [Member] \| OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Dividend payable date				Oct. 31, 2014
Holders of record date				Sep. 30, 2014
Dividends payable, date declared				Sep. 11, 2014
special dividend [Member] \| OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Distributions made to OP and LTIP units per unit (in dollars per share)			$ 2.25
OPP Units 2011 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Accelerated compensation expenses related To 2011 OPP Units				$ 1,200,000