Noncontrolling Interest (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) property	Mar. 31, 2020 USD ($)
Noncontrolling Interest
Net income attributable to noncontrolling interest	$ (1,322)	$ (1,408)
Cash distribution for joint venture partners	5,694	$ 5,767
Variable interest entity, consolidated, carrying amount, real estate assets	700,192
Variable interest entity, consolidated, carrying amount, mortgage debt	$ 620,000
Joint Venture
Noncontrolling Interest
Ownership percentage by noncontrolling owners	45.00%
Ownership percentage	55.00%
Boston, MA \| Life Science Building \| Joint Venture
Noncontrolling Interest
Number of properties included in joint venture agreement \| property	1

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