Aggregate Shares Issued

No definition available.

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- Definition

The aggregate market value of shares newly issued during the reporting period under the plan.

+ References

No definition available.

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- Definition

The number of unvested shares, that will vest in four years.

+ References

No definition available.

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- Definition

The number of unvested shares, that will vest in next fiscal year.

+ References

No definition available.

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- Definition

The number of unvested shares, that will vest in three years.

+ References

No definition available.

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- Definition

The number of unvested shares, that will vest in two years.

+ References

No definition available.

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- References

No definition available.

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- Definition

Represents the market value of shares, newly issued during the reporting period under the plan, to each individual.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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- Definition

Number of shares purchased for issuance under share-based payment arrangement.

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Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jan. 14, 2021	Jan. 01, 2020	Mar. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Scheduled to vest unvested shares
Share-based compensation expense				$ 1,568	$ 1,388	$ 2,224
Distributions to shareholders				$ 42,825	$ 199,719	$ 370,746
Five Star
Scheduled to vest unvested shares
Aggregate shares issued (shares)					16,118,849
Subsequent Event
Scheduled to vest unvested shares
Common distributions declared (in dollars per share)	$ 0.01
Distributions to shareholders	$ 2,383
Certain our Officers and Employees of RMR LLC
Scheduled to vest unvested shares
Shares purchased from certain of our officers and other employees of RMR LLC (in shares)				47,375	31,747	22,999
Five Star
Share-based Compensation Arrangement by Share-based Payment Award
Market value of shares awarded to each Trustee		$ 59,801
Share Award Plans
Share-based Compensation Arrangement by Share-based Payment Award
Remaining common shares available for issuance (in shares)				1,843,617
Number of unvested shares (in shares)				434,550	227,340	161,990	148,010
Scheduled to vest unvested shares
2021 (in shares)				158,330
2022 (in shares)				111,920
2023 (in shares)				97,900
2024 (in shares)				66,400
Estimated future compensation for the unvested shares				$ 2,205
Weighted average period over which the compensation expense will be recorded				1 year 10 months 24 days
Officers and Employees \| Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares)				360,000	187,500	105,800
Aggregate market value of shares awarded				$ 1,357	$ 1,633	$ 2,022
Award vesting period				5 years
Trustees \| Share Award Plans
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares)			3,000
Aggregate market value of shares awarded			$ 47
Trustees \| Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares)				10,000	3,000	3,000
Aggregate market value of shares awarded				$ 176	$ 119	$ 248
Market value of shares awarded to each Trustee				$ 29	$ 24	$ 50