Number of shares delivered of equity interests owned of a related party to acquire an entity.

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Cash Received for Issuance of Shares and Contribution of Property

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Represents the closing price of the common shares on the date of Up-C Transaction.

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Contribution of Ownership, Percentage

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Payments to Related Party, Tax Receivable Agreement

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Registration Rights and Lock-Up Agreement, Restriction Period of Transferring Acquired Shares

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Represents the value of consideration received from a related party at a discount with respect to the Up-C Transaction. This amount was recorded in other assets and being amortized on a the straight-line basis as a reduction of future revenue.

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Represents the carrying amount on the reporting date of the current and non current obligations relating to the tax receivable agreement.

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Represents the percent of cash savings, if any, in US Federal, state and local income tax or francishe tax provided in the Tax Receivable Agreement with a related party.

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No definition available.

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- Definition

Represents the management agreement term in years.

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No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Amount of cash distribution paid to unit-holder of limited liability company (LLC).

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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Amount of noncurrent assets classified as other.

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Amount of expense charged against earnings to allocate the cost of tangible and intangible assets over their remaining economic lives, classified as other.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- Definition

The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible 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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Related Party Transactions - Up C Transaction (Details) - USD ($) $ in Thousands				4 Months Ended	12 Months Ended
	Dec. 14, 2015	Jun. 05, 2015	Jun. 04, 2015	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	May 19, 2016
Related Party Transaction [Line Items]
Proceeds from sale of personal property					$ 0	$ 1,335	$ 25
Cash consideration					2,479	0	0
General and administrative expense					25,129	26,535	$ 21,957
Other assets, net of amortization				$ 190,807	$ 181,391	190,807
Up C Transaction
Related Party Transaction [Line Items]
Restriction period of transferring acquired common shares (in years)					10 years
Managed REITs \| Up C Transaction
Related Party Transaction [Line Items]
Term of management agreement (in years)		20 years
Related party consideration Up C Transaction		$ 193,806
Amortization of other assets					$ 9,416	$ 2,999
ABP Trust \| Up C Transaction
Related Party Transaction [Line Items]
Tax receivable agreement, percent of payment					85.00%
Payments pursuant to Tax Receivable Agreement					$ 905
Tax receivable agreement amount payable		$ 65,834			64,929
The Founders \| Up C Transaction
Related Party Transaction [Line Items]
Ownership percentage contributed		100.00%
RMR LLC \| Up C Transaction
Related Party Transaction [Line Items]
General and administrative expense				$ 5,454
RMR LLC \| ABP Trust and Managed REIT
Related Party Transaction [Line Items]
Distributions paid					63,095
RMR LLC \| ABP Trust
Related Party Transaction [Line Items]
Distributions paid					$ 30,533
Managed REITs \| Up C Transaction
Related Party Transaction [Line Items]
Closing price of common shares (in dollars per share)		$ 121,378
ABP Trust \| Up C Transaction
Related Party Transaction [Line Items]
Cash consideration		11,520
GOV \| Up C Transaction
Related Party Transaction [Line Items]
Cash consideration		3,917
HPT \| Up C Transaction
Related Party Transaction [Line Items]
Cash consideration		12,622
SIR \| Up C Transaction
Related Party Transaction [Line Items]
Cash consideration		15,880
SNH \| Up C Transaction
Related Party Transaction [Line Items]
Cash consideration		$ 13,967
Common shares \| GOV \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		700,000
Common shares \| HPT \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		1,490,000
Common shares \| SIR \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		880,000
Common shares \| SNH \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		2,345,000
Class B-1 common shares \| ABP Trust \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		1,000,000
Class B-2 common shares \| ABP Trust \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		15,000,000
Class A common shares \| SNH
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		5,272,787
Class A common shares \| SIR
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		3,166,891
Class A common shares \| HPT
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		5,019,121
Class A common shares \| GOV
Related Party Transaction [Line Items]
Number of shares distributed (in shares)		1,541,201
Class A common shares \| GOV
Related Party Transaction [Line Items]
Common stock shares outstanding	441,056
Class A common shares \| GOV \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)	768,032
Class A common shares \| HPT \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)	2,515,344
Class A common shares \| SIR \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)	1,580,055
Class A common shares \| SNH \| Up C Transaction
Related Party Transaction [Line Items]
Number of shares distributed (in shares)	2,635,379
Class A membership units \| ABP Trust \| RMR LLC
Related Party Transaction [Line Items]
Shares delivered (in shares)		15,000,000	30,000,000
Class A common shares
Related Party Transaction [Line Items]
Common stock shares outstanding				15,000,000	15,082,432	15,000,000
Class A common shares \| Managed REITs
Related Party Transaction [Line Items]
Payment made to acquire common shares		$ 167,764
Class A common shares \| Managed REITs \| Up C Transaction
Related Party Transaction [Line Items]
Payment made to acquire common shares		$ 167,764
Common stock shares outstanding		15,000,000
Class A common shares \| ABP Trust
Related Party Transaction [Line Items]
Common stock shares outstanding								15,000,000
Eliminations \| RMR LLC
Related Party Transaction [Line Items]
Distributions paid					$ 32,562
RMR, Inc \| Class A common shares \| Managed REITs \| Up C Transaction
Related Party Transaction [Line Items]
Ownership percentage by noncontrolling owners, more than					5.00%
Sonesta \| ABP Trust \| Up C Transaction
Related Party Transaction [Line Items]
Proceeds from sale of personal property		$ 1,335