v2.4.0.8

(Common Units) (Narrative) (Details) (USD $) | 0 Months Ended | 9 Months Ended |
--- | --- | --- | ---
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 |

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