Unsecured Senior Notes Unsecured Senior Notes (Narrative) (Details) - USD ($) $ in Thousands			12 Months Ended
	Aug. 17, 2016	Jan. 20, 2016	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Maximum Secured Debt Leverage Ratio			55.00%
Proceeds from unsecured senior notes			$ 1,989,790		$ 0	$ 0
Senior Notes [Member]
Debt Instrument [Line Items]
Maximum Leverage Ratio			60.00%
Maximum Secured Debt Leverage Ratio			50.00%
Minimum Interest Coverage Ratio			1.50
Minimum Unencumbered Asset Value Percentage Of Unsecured Debt			150.00%
Boston Properties Limited Partnership
Debt Instrument [Line Items]
Proceeds from unsecured senior notes			$ 1,989,790		$ 0	$ 0
Boston Properties Limited Partnership | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 7,300,000
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Note 3.766%
Debt Instrument [Line Items]
Coupon/Stated Rate		3.65%	3.65%
Senior Notes Pricing		99.708%
Effective Rate		3.766%	3.766%	[1]
Proceeds from unsecured senior notes		$ 988,900
Long-term Debt, Gross		$ 1,000,000	$ 1,000,000
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Note 3.495%
Debt Instrument [Line Items]
Coupon/Stated Rate	2.75%		2.75%
Senior Notes Pricing	99.271%
Effective Rate	3.495%		3.495%	[1]
Proceeds from unsecured senior notes	$ 984,700
Long-term Debt, Gross	$ 1,000,000		$ 1,000,000

[1] Yield on issuance date including the effects of discounts on the notes, settlements of interest rate contracts and the amortization of financing costs.