Net Income Attributable to RMR Inc. - Additional Information (Details) - RMR LLC	8 Months Ended
Jun. 04, 2014
Noncontrolling Interest [Line Items]
Percentage of income earned by noncontrolling interest	100.00%
ABP Trust
Noncontrolling Interest [Line Items]
Ownership percentage	100.00%

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.

No definition available.

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