v2.4.0.8

(Common Units) (Narrative) (Details) (USD $) | 0 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Apr. 30, 2013 | Jan. 29, 2013 | Jun. 30, 2013 Y | Jun. 18, 2013
OP Units [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
OP Units for redemption (in shares) |  |  | 333,997 |
Redemption of OP units issued on conversion of LTIP Units (in shares) |  |  | 17,651 |
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 |  |
Distribution paid to outperformance awards, OPP Units (in dollars per share) | $ 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 |  |  | $ 1,800,000,000 |
Value of Series Two Preferred Units assuming conversion |  |  | $ 137,900,000 |
OPP Units 2011 [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Outperformance awards in LTIP Units (in shares) |  |  | 397,750 |
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) |  |  | 397,750 |
OP Units [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Closing price of common stock (in dollars per share) |  |  | $ 105.47 |
Quarter 4 2012 [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Jan. 29, 2013 |
Quarter 4 2012 [Member] | OP Units [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Jan. 29, 2013 |
Holders of record date |  |  | Dec. 31, 2012 |
Quarter 1 2013 [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Apr. 30, 2013 |
Quarter 1 2013 [Member] | OP Units [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Apr. 30, 2013 |
Holders of record date |  |  | Mar. 29, 2013 |
Quarter 2 2013 [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Jul. 31, 2013 |
Dividends payable, date declared |  |  | Jun. 18, 2013 |
Quarter 2 2013 [Member] | OP Units [Member] |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |
Dividend payable date |  |  | Jul. 31, 2013 |
Holders of record date |  |  | Jun. 28, 2013 |
Dividends payable, date declared |  |  | Jun. 18, 2013 |

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