Net Income Attributable to RMR Inc (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Net income before income tax expense	$ 81,693	$ 19,620
Less: incentive fee allocable to ABP Trust	(26,611)
Net income before non-controlling interest	55,082
Less: non-controlling interest (48.4%)	(26,714)
Net income attributable to RMR Inc. before income tax expense	28,368
Less: income tax expense attributable to RMR Inc.	(11,314)
Net income attributable to RMR Inc.	$ 17,054
Ownership percentage by noncontrolling owners	48.40%
RMR LLC
Less: income tax expense attributable to RMR Inc.		$ 0