Consolidated Statement of Partners' Capital Statement - USD ($) $ in Thousands	Total	Boston Properties Limited Partnership
Beginning balance at Dec. 31, 2015		$ 3,684,522
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions		3,144
Net income allocable to general and limited partner units		526,581
Distributions		(425,527)
Other comprehensive Income (loss)		(38,137)
Unearned compensation		2,760
Conversion of redeemable partnership units		6,461
Adjustment to reflect redeemable partnership units at redemption value		51,913
Ending Balance at Dec. 31, 2016		3,811,717
Increase (Decrease) in Partners' Capital [Roll Forward]
Cumulative effect of a change in accounting principle	$ (2,035)	(272)
Contributions		4,937
Net income allocable to general and limited partner units		471,156
Distributions		(480,816)
Accumulated Other Comprehensive Loss Allocable To General And Limited Partner Units		1,822
Unearned compensation		(243)
Conversion of redeemable partnership units		16,916
Adjustment to reflect redeemable partnership units at redemption value		(17,587)
Ending Balance at Dec. 31, 2017		3,807,630
Increase (Decrease) in Partners' Capital [Roll Forward]
Cumulative effect of a change in accounting principle	$ 5,496	4,933
Contributions		1,642
Net income allocable to general and limited partner units		600,596
Distributions		(550,971)
Accumulated Other Comprehensive Loss Allocable To General And Limited Partner Units		2,688
Unearned compensation		884
Conversion of redeemable partnership units		2,880
Adjustment to reflect redeemable partnership units at redemption value		330,596
Ending Balance at Dec. 31, 2018		$ 4,200,878

Accumulated Other Comprehensive Loss Allocable To General And Limited Partner Units.

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Aggregate Partners Capital (inclusive of Series B Preferred Units)

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Net Income Allocable To General And Limited Partner Units

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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Total change in each class of partners' capital accounts during the year due to deferred compensation. Partners include general, limited and preferred partners.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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Total change in each class of partners' capital accounts during the year due to exchanges and conversions. Partners include general, limited and preferred partners.

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Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

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