Disposal Group, Number Of Communities Disposed Of

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- Definition

Master Leases Not Renewed, Number Of Communities

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- Definition

Number Of Communities Managed

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- Definition

Number Of Lease Portfolios

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- Definition

Number Of Leases Not Renewed

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- Definition

Operating Leases, Base Rent

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- Definition

Operating Leases, Number Of Communities

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- Definition

Payments (Proceeds) For Lease Termination

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- Definition

Potential Lease Terminations, Rent Credit Percentage

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- Definition

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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- Definition

Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries or equity method investee.

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- Definition

Amount of gain (loss) on termination of lease before expiration of lease term.

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- Definition

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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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Acquisitions, Dispositions and Other Significant Transactions - Welltower Lease and RIDEA Venture Restructuring (Details) $ in Thousands		3 Months Ended		12 Months Ended			36 Months Ended
	Jun. 30, 2018 USD ($) community lease_portfolio	Jun. 30, 2019 USD ($) community	Jun. 30, 2018 USD ($)	Dec. 31, 2020 USD ($) lease	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) community	Dec. 31, 2019 community	Sep. 30, 2018 lease community
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities leased \| lease				235
Payments for lease termination				$ 0	$ 0	$ 12,548
Loss on facility lease termination and modification, net				$ (2,303)	$ 3,388	$ 162,001
Ownership Percentage				50.00%
Master leases not renewed, number of communities \| community								11
37 Communities Disposed Of Through Lease Terminations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities disposed of \| community							147
Welltower Lease Transactions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of leases not renewed \| lease								2
Number of communities managed \| community						74
Welltower Lease Transactions \| 37 Communities Disposed Of Through Lease Terminations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities disposed of \| community	37
Welltower Inc. \| Welltower Lease Transactions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of lease portfolios \| lease_portfolio	2
Payments for lease termination		$ 58,000
Loss on facility lease termination and modification, net						$ (22,600)
Rent credit, potential future lease terminations	6.25%
Proceeds from sale of equity method investment			$ 33,500
Gain on sale of equity method investment			$ 14,700
Welltower Inc. \| Welltower Lease Transactions, Lease Portfolio Maturing In 2028
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities leased \| community		27
Welltower Inc. \| Welltower Lease Transactions, Lease Portfolio Maturing In 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities leased \| community		10
Maximum \| Welltower Inc. \| Welltower Lease Transactions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Base rent	$ 5,000
Welltower RIDEA
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership Percentage	20.00%		20.00%