Noncontrolling Interest (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) building property	Jun. 30, 2018 USD ($)
Noncontrolling Interest [Line Items]
Comprehensive income attributable to noncontrolling interest	$ (1,413)	$ (1,401)	$ (2,835)	$ (2,784)
Cash distribution for joint venture partners	5,684	$ 5,114	11,187	$ 10,781
Variable interest entity, consolidated, carrying amount, real estate assets	735,133		735,133
Variable interest entity, consolidated, carrying amount, mortgage debt	$ 620,000		$ 620,000
Joint Venture
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners	45.00%		45.00%
Ownership percentage	55.00%		55.00%
Massachusetts \| MOBs \| Joint Venture
Noncontrolling Interest [Line Items]
Number of properties included in joint venture agreement \| property			1
Number of buildings included in joint venture agreement \| building			2

Number of Buildings Included in Joint Venture Agreement

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Number of Properties Included in Joint Venture Agreement

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Variable Interest Entity, Consolidated, Carrying Amount, Mortgage Debt

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Variable Interest Entity, Consolidated, Carrying Amount, Real Estate Assets

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

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