Derivative and Hedging Instruments Derivative Instruments and Hedging Activities Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Beginning Balance		$ (52,251)	$ (14,114)	$ (9,304)
Effective portion of interest rate contracts		(6,133)	(47,144)	(10,302)
Amortization of interest rate contracts	[1]	6,033	3,751	2,510
Other comprehensive loss attributable to noncontrolling interests		1,922	5,256	2,982
Ending Balance		(50,429)	(52,251)	(14,114)
Boston Properties Limited Partnership
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Beginning Balance		(60,853)	(18,337)	(12,973)
Effective portion of interest rate contracts		(6,133)	(47,144)	(10,302)
Amortization of interest rate contracts	[2]	6,033	3,751	2,510
Other comprehensive loss attributable to noncontrolling interests		2,128	877	2,428
Ending Balance		$ (58,825)	$ (60,853)	$ (18,337)

[1] Amounts reclassified from comprehensive income primarily to interest expense within Boston Properties, Inc.’s Consolidated Statements of Operations

[2] Amounts reclassified from comprehensive income primarily to interest expense within Boston Properties Limited Partnership's Consolidated Statements of Operations.