Management Agreements

No definition available.

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- Definition

Represents the minimum percentage of common stock held in the investee above which the entity would have the option to cancel all its rights.

+ References

No definition available.

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- Definition

Related Party Transaction, Closing Cost

+ References

No definition available.

+ Details

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- Definition

Represents the maximum percentage of the equity shares of the entity which any single person or group can acquire without obtaining approval.

+ References

No definition available.

+ Details

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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- Definition

Balance held at close of period in number of shares.

+ References

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Balance Type:	na
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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Related Person Transactions (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) agreement shares	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Feb. 28, 2023 $ / shares
Related Party Transaction
Revenue	$ 1,283,566	$ 1,383,212	$ 1,632,026
Subsequent Event \| AlerisLife Inc
Related Party Transaction
Investment in equity securities acquisition, share price (in dollars per share) \| $ / shares				$ 1.31
Common stock proposed acquisition percentage				31.90%
Rental income
Related Party Transaction
Revenue	$ 260,740	408,589	427,215
AlerisLife Inc
Related Party Transaction
Investment in common shares (in shares) \| shares	10,691,658
Ownership interest by parent	31.90%
Affiliated Entity
Related Party Transaction
Minimum percentage of ownership of lessee's voting stock above which the entity has the option to cancel all its rights	9.80%
Reit Management And Research
Related Party Transaction
Related party transaction, closing cost	$ 8,715
AlerisLife Inc
Related Party Transaction
Maximum percentage of any class of equity shares that can be acquired without approval	9.80%
RMR
Related Party Transaction
Number of management agreements with related party \| agreement	2
RMR \| Rental income
Related Party Transaction
Revenue	$ 303	$ 190	$ 163
ABP Acquisition LLC \| AlerisLife Inc
Related Party Transaction
Ownership interest by noncontrolling owners	6.10%
RMR \| Year one
Related Party Transaction
Award vesting rights, percentage	20.00%
RMR \| Year two
Related Party Transaction
Award vesting rights, percentage	20.00%
RMR \| Year three
Related Party Transaction
Award vesting rights, percentage	20.00%
RMR \| Year four
Related Party Transaction
Award vesting rights, percentage	20.00%
RMR \| Year five
Related Party Transaction
Award vesting rights, percentage	20.00%