Represents the number of trustees in equity compensation plan.

No definition available.

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- Definition

Stock Repurchased During Period, Price Per Share

+ References

No definition available.

+ Details

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Balance Type:	na
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- Definition

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

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Balance Type:	credit
Period Type:	instant

- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ 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

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Period Type:	duration

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- Details

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- Details

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Shareholders' Equity (Details) $ / shares in Units, $ in Thousands											3 Months Ended					9 Months Ended
	Oct. 17, 2019 USD ($) $ / shares	Sep. 25, 2019 $ / shares shares	Sep. 18, 2019 $ / shares shares	Aug. 15, 2019 USD ($) $ / shares	Jul. 03, 2019 $ / shares shares	May 29, 2019 trustee $ / shares shares	May 16, 2019 USD ($) $ / shares	Apr. 05, 2019 $ / shares shares	Feb. 27, 2019 trustee $ / shares shares	Feb. 21, 2019 USD ($) $ / shares	Sep. 30, 2019 shares	Jun. 30, 2019 shares	Sep. 30, 2018 shares	Jun. 30, 2018 shares	Mar. 31, 2018 shares	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Share Awards
Cash distribution to common shareholders (in dollars per share)				$ 0.55			$ 0.55			$ 0.55
Distributions to common shareholders \| $							$ 26,450			$ 26,445						$ 79,356	$ 127,907
Dividends declared \| $				$ 26,461
Subsequent Event
Share Awards
Dividends declared (in dollars per share)	$ 0.55
Dividends declared \| $	$ 26,500
Officers and Other Employees of RMR LLC
Share Awards
Share repurchase price (in dollars per share)		$ 30.41
Stock Repurchased During Period, Shares \| shares		11,433
Former Employee of RMR LLC
Share Awards
Share repurchase price (in dollars per share)					$ 27.73	$ 23.97		$ 28.96
Stock Repurchased During Period, Shares \| shares					1,779	450		1,795
Common shares
Share Awards
Stock Repurchased During Period, Shares \| shares											13,212	2,245	4,838	113	153
Common shares \| Trustees
Share Awards
Number of trustees \| trustee						8			3
Shares granted (in shares) \| shares						3,000			3,000
Shares granted (in dollars per share)						$ 23.97			$ 29.95
Common shares \| Officers and Other Employees of RMR LLC
Share Awards
Shares granted (in shares) \| shares			103,100
Shares granted (in dollars per share)			$ 29.87