(Common Units) (Narrative) (Details) $ / shares in Units, $ in Millions			3 Months Ended
	Feb. 04, 2016 USD ($) shares	Feb. 06, 2015 USD ($) shares	Mar. 31, 2016 USD ($) yr $ / shares shares
OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
OP Units for redemption (in shares)			13,259
Redemption of OP units issued on conversion of LTIP Units (in shares)			7,277
Restriction on redemption of OP Unit to Common Stock (in years) | yr			1
Redemption of OP Unit equivalence to Common Stock (in shares)			1
Common units of operating partnership if converted value | $			$ 2,300.0
Closing price of common stock (in dollars per share) | $ / shares			$ 127.08
OPP Units 2012 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Outperformance awards earned | $		$ 32.1
Potential maximum amount of Outperformance Awards earned (percent)		80.00%
Potential Awards Earned | $		$ 40.0
2012 OPP Units Forfeited		174,549
2013 MYLTIP [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Final awards percentage of target	109.50%
Value of MYLTIP Awards | $	$ 13.5
2013 MYLTIP Units Forfeited	205,762
Boston Properties Limited Partnership | OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Outperformance Awards LTIP Units distribution as percentage of OP Unit distribution prior to measurement date			10.00%
Boston Properties Limited Partnership | MYLTIP 2014 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
2014 MYLTIP (in units)			475,558
Boston Properties Limited Partnership | 2015 MYLTIP [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
2015 MYLTIPS (in units)			367,936
Boston Properties Limited Partnership | 2016 MYLTIP [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
2016 MYLTIPs (in units)			474,456