Noncontrolling Interests Common units for Boston Properties Limited Partnership (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Noncontrolling Interest [Line Items]
Conversion of redeemable partnership units		$ 0
Cumulative effect of a change in accounting principle	$ (2,035)
Accumulated other comprehensive income (loss)	(51,796)	(73,943)	$ (52,251)	$ (14,114)
Noncontrolling Interests [Member]
Noncontrolling Interest [Line Items]
Conversion of redeemable partnership units	16,986	10,094
Cumulative effect of a change in accounting principle	(1,763)
Boston Properties Limited Partnership
Noncontrolling Interest [Line Items]
Cumulative effect of a change in accounting principle	(272)
Accumulated other comprehensive income (loss)	(60,346)	(85,043)	$ (60,853)	$ (18,337)
Boston Properties Limited Partnership | Noncontrolling Interests [Member]
Noncontrolling Interest [Line Items]
Beginning balance	2,262,040	2,286,689
Contributions	31,465	31,492
Net income	40,350	42,120
Distributions	(40,292)	(35,500)
Conversion of redeemable partnership units	(16,812)	(5,881)
Unearned compensation	(5,194)	(10,072)
Cumulative effect of a change in accounting principle	(1,763)
Accumulated other comprehensive income (loss)	52	(6,877)
Adjustments to reflect redeemable preferred units at redemption value	(103,556)	151,545
Ending balance	$ 2,166,290	$ 2,453,516