Amount of committed but unspent tenant related obligations based on executed lease.

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Represents the amount of expenditure committed by entity relating to leases.

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Number Of Properties Included In Joint Venture Agreement

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Number of Real Estate Properties Closed

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Percentage Of Equity Method Investment Sold

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Represents the aggregate purchase price excluding acquisition costs of real estate properties acquired or agreed to be acquired by the entity.

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This element represents the aggregate sales price excluding closing costs, of real estate properties sold by the entity.

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Real Estate Property Fair Value

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Related Party Transaction, Amount Of Improvements To Communities To Leased Asset

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower and amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Area of a real estate property.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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The number of real estate properties owned as of the balance sheet date.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Real Estate Investments - Narrative (Details) $ in Thousands		1 Months Ended				12 Months Ended
	Dec. 23, 2021	Jan. 31, 2022 USD ($) property	Dec. 31, 2021 USD ($) ft² building property community unit	Jan. 31, 2020 USD ($)	May 31, 2019 USD ($) unit building	Dec. 31, 2021 USD ($) ft² property building community unit	Dec. 31, 2020 USD ($) ft² property building	Dec. 31, 2019 USD ($) ft² unit building property	Jun. 09, 2021 unit community	Sep. 30, 2019 property	Mar. 31, 2017
Real Estate Properties
Real estate investment properties, net			$ 5,075,749			$ 5,075,749	$ 5,715,829
Real estate property - accumulated depreciation			$ 1,737,807			$ 1,737,807	1,694,901
Number of properties owned (property) \| property			390			390
Total assets			$ 6,623,514			$ 6,623,514	6,476,424	$ 6,653,826
Secured debt and finance leases, net			69,713			69,713	691,573
Proceeds from sale of interest in joint venture, net						367,033	0	0
Gain on sale of properties						492,272	6,487	39,696
Equity method investments, carrying value			31,540			31,540	73,772
Impairment of assets						(174)	106,972	$ 115,201
Lease committed but unspent tenant related obligations						76,573	19,159
Variable Interest Entity, Primary Beneficiary
Real Estate Properties
Total assets							970,142
Secured debt and finance leases, net							697,129
Seaport Innovation LLC
Real Estate Properties
Aggregate property valuation amount			1,700,000			1,700,000
Aggregate principal amount of mortgage debt			620,000			620,000
Land
Real Estate Properties
Real estate investment properties, net			741,501			741,501	789,125
Buildings and Improvements
Real Estate Properties
Real estate investment properties, net			6,072,055			6,072,055	6,621,605
Building
Real Estate Properties
Real estate property - accumulated depreciation			1,587,573			1,587,573	1,561,751
Building Improvements
Real Estate Properties
Real estate property - accumulated depreciation			$ 150,234			$ 150,234	$ 133,150
Medical Office Building
Real Estate Properties
Number of properties owned (property) \| property							7	20
Impairment of assets							$ 8,558	$ 43,035
Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| property							28	25
Number of units in real estate property \| unit			27,672			27,672
Gain on sale of properties							$ 225
Impairment of assets							$ 98,414	$ 72,166
Welness Centers
Real Estate Properties
Number of properties owned (property) \| property			10			10
Area of real estate properties (in square feet) \| ft²			812,000			812,000
SNF
Real Estate Properties
Gain on sale of properties						$ 200
Life Science
Real Estate Properties
Number of properties owned (property) \| property								1
Medical Office Building and Life Science Building
Real Estate Properties
Number of properties owned (property) \| property			116			116
Area of real estate properties (in square feet) \| ft²			9,800,000			9,800,000
Medical Office Building and Life Science Building \| Capital Commitments
Real Estate Properties
Area of real estate properties (in square feet) \| ft²			2,600,000			2,600,000	1,000,000
Leases committed expenditure						$ 97,520	$ 17,901
Medical Office Building and Life Science Building \| Subsequent Event \| Unrelated Investor One
Real Estate Properties
Equity method investments, carrying value		$ 100,800
Medical Office Building and Life Science Building \| Subsequent Event \| Unrelated Investor Two
Real Estate Properties
Equity method investments, carrying value		95,900
Senior Living Communities, Independent Living, Assisted Living, and Skilled Nursing Facility
Real Estate Properties
Number of properties owned (property) \| property			264			264
Land Parcel \| Arizona
Real Estate Properties
Real estate purchase price				$ 2,600
Joint Venture
Real Estate Properties
Gain on sale of properties			$ 461,434
Joint Venture \| Seaport Innovation LLC
Real Estate Properties
Number of properties owned (property) \| property			1			1
Area of real estate properties (in square feet) \| ft²			1,134,479			1,134,479
Number of properties included in joint venture agreement \| property						1
Equity method investment ownership percentage	20.00%		20.00%			20.00%					55.00%
Additional equity joint venture percentage	35.00%		35.00%
Proceeds from sale of interest in joint venture, net			$ 373,847
Joint Venture \| Investor \| Seaport Innovation LLC
Real Estate Properties
Equity method investment ownership percentage											45.00%
Joint Venture \| Subsequent Event
Real Estate Properties
Aggregate property valuation amount		702,500
Aggregate principal amount of mortgage debt		$ 456,600
Joint Venture \| Medical Office Building and Life Science Building \| Subsequent Event
Real Estate Properties
Number of properties included in joint venture agreement \| property		10
Equity method investment ownership percentage		20.00%
Proceeds from sale of interest in joint venture, net		$ 653,300
Joint Venture \| Medical Office Building and Life Science Building \| Subsequent Event \| Unrelated Investor One
Real Estate Properties
Equity method investment ownership percentage		41.00%
Joint Venture \| Medical Office Building and Life Science Building \| Subsequent Event \| Unrelated Investor Two
Real Estate Properties
Equity method investment ownership percentage		39.00%
Five Star \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| community									120
Five Star \| Five Star
Real Estate Properties
Amount of improvements to communities								$ 111,603
Payments to acquire property, plant, and equipment								$ 49,155
Scenario, Adjustment \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| property			10			10
Impairment of assets						$ (174)
Disposal Group, Held-for-sale, Not Discontinued Operations \| Medical Office Building
Real Estate Properties
Number of properties owned (property) \| property							1	15
Disposal Group, Held-for-sale, Not Discontinued Operations \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| property							10	2
Number of units in real estate property \| property							820
Disposal Group, Held-for-sale, Not Discontinued Operations \| Medical Office Building and Life Science Building
Real Estate Properties
Area of real estate properties (in square feet) \| ft²							355,656
Number of units in real estate property \| property							5
Disposal Group, Held-for-sale, Not Discontinued Operations \| Five Star \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| community			108			108			108
Number of units in real estate property \| unit									1,500
Disposal Group, Held-for-sale, Not Discontinued Operations \| Scenario, Adjustment \| Five Star \| Senior Living Communities
Real Estate Properties
Number of units in real estate property \| unit									7,500
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Real Estate Properties
Number of properties owned (property) \| building			5			5	27	46
Sale price of property sold and agreed to be sold						$ 104,500	$ 152,893	$ 260,783
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Medical Office Building
Real Estate Properties
Number of properties owned (property) \| property							4
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| property							9
Number of real estate properties closed \| property							7
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| SNF
Real Estate Properties
Number of properties owned (property) \| property			8			8
Number of units in real estate property \| property										15
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| SNF \| California
Real Estate Properties
Number of properties owned (property) \| building					3
Number of units in real estate property \| unit					278
Sale price of property sold and agreed to be sold					$ 21,500
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Medical Office Building and Life Science Building
Real Estate Properties
Number of properties owned (property) \| property								5
Discontinued Operations, Held-for-sale \| Senior Living Communities
Real Estate Properties
Number of properties owned (property) \| property								12
Number of units in real estate property \| unit								1,670
Discontinued Operations, Held-for-sale \| Medical Office Building and Life Science Building
Real Estate Properties
Number of properties owned (property) \| property								21
Area of real estate properties (in square feet) \| ft²								875,617
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations \| Medical Office Building
Real Estate Properties
Number of properties owned (property) \| property							10