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The initial other liabilities recorded which is the difference of the total consideration paid and the fair market value of the investment.

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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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Includes all other interest income, net of discount accretion and premium amortization, and dividend income. It may include dividend income from equity securities that do not have readily determinable fair values that are reportable in Other Assets, and interest income on interest-only strips receivable (not in the form of a security) that are included in Other Assets.

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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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Cumulative number of shares issued or sold by the subsidiary or equity method investee on all stock transactions.

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Related Person Transactions - REITs, for which RMR LLC provides Management Services (Details) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) company	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) company shares	Jun. 30, 2015 USD ($)	Jul. 12, 2016 $ / shares	Dec. 31, 2015 USD ($)
Related Person Transaction
Dividend received	$ 363		$ 363
Proceeds from Equity Method Investment, Dividends or Distributions			17,760	$ 10,425
Investment at carrying value	492,762		492,762			$ 491,369
Recognized income (loss) related to investment	9,400	$ 6,094	$ 19,334	5,778
SIR
Related Person Transaction
Shares holding \| shares			24,918,421
Quarterly dividend payable on common stock (in dollars per share) \| $ / shares					$ 0.51
Proceeds from Equity Method Investment, Dividends or Distributions	12,459	8,582	$ 24,918	22,112
Investment at carrying value	492,762		492,762
Recognized income (loss) related to investment	8,643	8,249	17,760	10,425
SIR \| SIR
Related Person Transaction
Dividend received	475		475
Recognized income (loss) related to investment	$ 17	23	$ 94	95
AIC
Related Person Transaction
Number of other companies owning outstanding shares \| company	6		6
Amount invested in equity investee	$ 7,135		$ 7,135			$ 6,946
Coverage of purchased property insurance			1,032
Recognized income (loss) related to investment	17	22	94	95
Other Comprehensive Income, Other, Net of Tax	43	(64)	95	(19)
RMR Inc
Related Person Transaction
Recognized amortization of the liability	272	$ 65	543	$ 65
RMR Inc
Related Person Transaction
Initial Other Liabilities	21,210		$ 21,210
RMR Inc \| Class A common shares
Related Person Transaction
Dividend received	$ 363
Shares holding \| shares			1,214,225
Quarterly dividend payable on common stock (in dollars per share) \| $ / shares					$ 0.25