Net Income Attributable to RMR Inc (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net Income Attributable to RMR Inc.
Net income before income tax expense	$ 21,906	$ 16,909	$ 123,433	$ 61,643
Add: RMR Inc. franchise tax expense and interest income	220		443
Incentive fee allocable to ABP Trust			(26,611)
Net income before non-controlling interest	22,126		97,265
Less: non-controlling interest	(10,704)		(47,052)
Net income attributable to RMR Inc. before income tax expense	11,422		50,213
Less: income tax expense attributable to RMR Inc.	(4,504)	(651)	(19,904)	(654)
Less: RMR Inc. franchise tax expense and interest income	(220)		(443)
Net income attributable to RMR Inc.	$ 6,698	$ 970	$ 29,866	$ 970