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- Definition

Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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

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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

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

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Amount of paid and unpaid cash dividends declared for award under share-based payment arrangement.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Shareholders’ Equity - Additional Information (Details) $ / shares in Units, $ in Thousands				3 Months Ended						9 Months Ended
	Jul. 27, 2020 USD ($) $ / shares shares	Jun. 23, 2020 $ / shares shares	Mar. 11, 2020 $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares	Mar. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares	Jun. 30, 2020 USD ($) vesting_installment $ / shares shares	Jun. 30, 2019 USD ($) $ / shares	Sep. 30, 2019 shares
Class of Stock [Line Items]
Number of Vesting Installments \| vesting_installment										5
General and administrative				$ 6,335			$ 7,670			$ 20,678	$ 22,112
Equity based compensation expense				$ 563			$ 452			$ 1,789	$ 1,395
Unvested shares outstanding (in shares) \| shares				109,210						109,210
RMR LLC \| RMR LLC
Class of Stock [Line Items]
Dividends paid (in dollars per share) \| $ / shares				$ 0.30	$ 0.30	$ 0.30	$ 0.30	$ 0.30	$ 0.30	$ 0.90	$ 0.90
Value of dividends				$ 9,394	$ 9,390	$ 9,391	$ 9,372	$ 9,369	$ 9,369	$ 28,175	$ 28,110
Vesting 2020
Class of Stock [Line Items]
Shares vesting (in shares) \| shares										39,910
Vesting 2021
Class of Stock [Line Items]
Shares vesting (in shares) \| shares										31,940
Vesting 2022
Class of Stock [Line Items]
Shares vesting (in shares) \| shares										23,280
Vesting 2023
Class of Stock [Line Items]
Shares vesting (in shares) \| shares										14,080
Class A Common Stock
Class of Stock [Line Items]
Shares granted during period shares (in shares) \| shares			3,000
Share price (in dollars per share) \| $ / shares			$ 31.28
General and administrative				$ 95						$ 564
Shares repurchased (in shares) \| shares										4,455
Shares repurchased during period										$ 155
Common stock shares outstanding (in shares) \| shares				15,315,445						15,315,445		15,302,710
Class A Common Stock \| ABP Trust
Class of Stock [Line Items]
Value of dividends				$ 4,500	$ 4,500	$ 4,500	$ 4,500	$ 4,500	$ 4,500	$ 13,500	$ 13,500
Common stock shares outstanding (in shares) \| shares				15,000,000						15,000,000
Class A and B-1 common shares
Class of Stock [Line Items]
Dividends paid (in dollars per share) \| $ / shares				$ 0.38	$ 0.38	$ 0.38	$ 0.35	$ 0.35	$ 0.35	$ 1.14	$ 1.05
Value of dividends				$ 6,200	$ 6,194	$ 6,195	$ 5,684	$ 5,680	$ 5,680	$ 18,589	$ 17,044
Class A and B-1 common shares \| RMR LLC
Class of Stock [Line Items]
Value of dividends				$ 4,894	$ 4,890	$ 4,891	$ 4,872	$ 4,869	$ 4,869	$ 14,675	$ 14,610
Nonemployee \| Class A Common Stock
Class of Stock [Line Items]
Shares granted during period shares (in shares) \| shares		3,000
Share price (in dollars per share) \| $ / shares		$ 31.66
Subsequent Event \| RMR LLC \| RMR LLC
Class of Stock [Line Items]
Value of dividends	$ 9,395
Subsequent Event \| Class A Common Stock \| ABP Trust
Class of Stock [Line Items]
Value of dividends	$ 4,500
Subsequent Event \| Class A and B-1 common shares
Class of Stock [Line Items]
Dividends paid (in dollars per share) \| $ / shares	$ 0.38
Value of dividends	$ 6,200
Common stock shares outstanding (in shares) \| shares	16,315,445
Subsequent Event \| Class A and B-1 common shares \| RMR LLC
Class of Stock [Line Items]
Dividends paid (in dollars per share) \| $ / shares	$ 0.30
Value of dividends	$ 4,895