Represent the amounts due from related person, owed to us from SIR related to working capital activity for MOBs.

No definition available.

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Represents the amount of premium payable for combined directors' and officers' liability insurance policy.

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No definition available.

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Represents the percentage of economic interest held in RMR Inc.

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No definition available.

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This element represents the amount of annual premiums including taxes and fees for property insurance pursuant to an insurance program arranged by the equity method investee.

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No definition available.

+ Details

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Represents the number of shares held as a percentage of the total shares outstanding at the end of the period.

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No definition available.

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Represents the number of the company's common shares under a lock up and registration rights agreement that are not authorized to be transferred for a specified period of time.

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No definition available.

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Represents the period over which the company's common shares remain under a lock up and registration rights agreement and not authorized to be transfered.

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No definition available.

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Represents the minimum percentage of common stock held in the investee above which the entity would have the option to cancel all its rights.

+ References

No definition available.

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Amount of non cash loss, which represents difference between our carrying value and the fair value of the RMR Inc. shares on the distribution date

+ References

No definition available.

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Represents the number of communities managed by a related party.

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Represents the number of properties acquired or agreed to be acquired by the entity.

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Represents the increase (decrease) in the entity's share of other comprehensive income of the investee.

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No definition available.

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Property Subject to or Available for Operating Lease, Number of Leases

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This element represents the aggregate purchase price of real estate properties acquired by the entity during the period. This amount includes cash paid plus debt assumed, if any, and other settlement adjustments but excludes closing costs.

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No definition available.

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Represents the debt disposed of in sale of property transactions.

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Related Party, Management Agreements

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Represents the cash purchase price paid to acquire common shares of beneficial interest of related party pursuant to the stock purchase agreement.

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Related Party Transaction, Percent of Shares Issued and Outstanding

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Represents the number of shares purchased, from related party.

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Related Party Transactions, Shares Authorized to Purchase

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Represents the aggregate fair value of the equity instruments other than options granted during the period.

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Represents the maximum percentage of the equity shares of the entity which any single person or group can acquire without obtaining approval.

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No definition available.

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Number of shares distributed to the shareholders.

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Represents the percentage of voting power controlled by a given entity with outstanding capital stock in RMR Inc.

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

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Balance held at close of period in number of shares.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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The number of units (items of property) under operating lease arrangements.

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No definition available.

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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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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Percentage of vesting of share-based compensation awards.

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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Related Person Transactions (Details)								1 Months Ended			3 Months Ended	12 Months Ended
Related Person Transactions (Details)	Nov. 10, 2016 $ / shares shares	Sep. 30, 2016 $ / shares shares	Sep. 26, 2016 $ / shares shares	Dec. 14, 2015 shares	Jun. 05, 2015 USD ($) shares	May 09, 2015 building	Jan. 29, 2015 USD ($) building	Sep. 30, 2015 USD ($) $ / shares shares	May 31, 2015 USD ($)	Jan. 31, 2015 USD ($) living_unit	Dec. 31, 2015 USD ($) community	Dec. 31, 2016 USD ($) community lease_agreement property agreement shares	Dec. 31, 2015 USD ($) community property shares	Dec. 31, 2014 USD ($) community property shares	Dec. 31, 2010
Related Party Transaction [Line Items]
Share price (in dollars per share) \| $ / shares								$ 16.19
Loss on distribution to common shareholders of The RMR Group Inc. common stock											$ 38,437,000	$ 0	$ 38,437,000	$ 0
Fair value adjustment, liabilities												3,600,000
Equity in earnings of an investee												137,000	20,000	87,000
Other comprehensive income (loss) attributable to equity method investee, net of tax												$ (152,000)	20,000	(2,000)
Acquisition
Related Party Transaction [Line Items]
Number of properties acquired or agreed to be acquired \| living_unit										23
The RMR Group Inc
Related Party Transaction [Line Items]
Investment in common shares \| shares												2,637,408
Economic interest percent												51.90%
Voting power percent												91.50%
Related party transaction, rate												3.00%
RMR Inc. \| Class A common shares
Related Party Transaction [Line Items]
Loss on distribution to common shareholders of The RMR Group Inc. common stock											$ 38,437,000
RMR Inc. \| Up C Transaction
Related Party Transaction [Line Items]
Cash purchase price					$ 13,967,000
RMR Inc. \| Up C Transaction \| Common Shares
Related Party Transaction [Line Items]
Shares issued in connection with acquisition \| shares					2,345,000
RMR LLC
Related Party Transaction [Line Items]
Rental revenue from related party												$ 242,000	$ 204,000	$ 0
RMR Inc. \| Class A common shares
Related Party Transaction [Line Items]
Shares distributed to stockholders \| shares				2,635,379
RMR Inc. \| Up C Transaction \| Managing Trustees Barry And Adam Portnoy
Related Party Transaction [Line Items]
Number of shares under lock up and registration agreement \| shares													2,345,000
Period over which shares remain under lock up and registration agreement													10 years
RMR Inc. \| RMR Inc. \| Up C Transaction \| Class B2 common shares
Related Party Transaction [Line Items]
Shares issued in connection with acquisition \| shares					5,272,787
Senior Living Communities
Related Party Transaction [Line Items]
Number of properties acquired or agreed to be acquired \| property													39	2
Senior Living Communities \| Acquisition
Related Party Transaction [Line Items]
Purchase price excluding closing costs and working capital adjustments								$ 18,250,000	$ 9,750,000
MOBs
Related Party Transaction [Line Items]
Number of properties acquired or agreed to be acquired \| living_unit										23
MOBs \| Acquisition
Related Party Transaction [Line Items]
Number of properties acquired or agreed to be acquired \| property												3	23	2
Purchase price excluding closing costs and working capital adjustments										$ 539,000,000
MOBs \| SIR \| Acquisition
Related Party Transaction [Line Items]
Debt disposed of from properties sold							$ 29,995,000
Amount from SIR related to working capital activity							$ 1,316,000
Five Star
Related Party Transaction [Line Items]
Percentage of total shares outstanding												8.50%			100.00%
Investment in common shares \| shares												4,235,000
Maximum percentage of any class of equity shares that can be acquired without approval												9.80%
Minimum percentage of ownership of lessee's voting stock above which the entity has the option to cancel all its rights												9.80%
Number of real estate properties leased \| community											177	185	177	181
Property subject to or available for operating lease, number of leases \| lease_agreement												5
Related party transaction, shares purchased \| shares	17,999,999
Related party transactions, shares authorized to purchase \| shares	18,000,000
Related party transaction, percent of shares issued and outstanding	38.00%
Share price (in dollars per share) \| $ / shares	$ 3.00
Five Star \| RMR LLC
Related Party Transaction [Line Items]
Percentage of total shares outstanding												36.70%
Investment in common shares \| shares												18,339,621
Five Star \| Senior Living Communities
Related Party Transaction [Line Items]
Number of communities managed \| community												68	60	46
RMR LLC
Related Party Transaction [Line Items]
Number of management agreements with related party \| agreement												2
Repurchase of common shares (in shares) \| shares								13,113
Shares issued in connection with acquisition \| shares													81,557
Premium payable for combined directors' and officers' liability insurance policy											$ 472,000	$ 142,000	$ 472,000	$ 736,000
RMR LLC \| Restricted shares
Related Party Transaction [Line Items]
Number of shares granted under the award plan \| shares												79,650	84,000	81,700
Aggregate value of awards granted during the period												$ 1,724,000	$ 1,321,000	$ 1,750,000
SIR \| MOBs \| Acquisition
Related Party Transaction [Line Items]
Number of properties acquired or agreed to be acquired \| building						23	23
Purchase price excluding closing costs and working capital adjustments							$ 532,000,000
Fair value adjustment, liabilities							$ 7,677,000
AIC
Related Party Transaction [Line Items]
Total premiums including taxes and fees												3,607,000	2,785,000	$ 3,118,000
Equity method investments, carrying value											$ 6,827,000	$ 7,116,000	$ 6,827,000
Purchase One
Related Party Transaction [Line Items]
Shares paid for tax withholding for share based compensation (in shares) \| shares			17,667
Share price (in dollars per share) \| $ / shares			$ 23.53
Purchase Two
Related Party Transaction [Line Items]
Shares paid for tax withholding for share based compensation (in shares) \| shares		1,563
Share price (in dollars per share) \| $ / shares		$ 22.71
Year one \| RMR LLC \| RMR Inc.
Related Party Transaction [Line Items]
Award vesting rights, percentage												20000.00%
Year two \| RMR LLC \| RMR Inc.
Related Party Transaction [Line Items]
Award vesting rights, percentage												20000.00%
Year three \| RMR LLC \| RMR Inc.
Related Party Transaction [Line Items]
Award vesting rights, percentage												20000.00%
Year four \| RMR LLC \| RMR Inc.
Related Party Transaction [Line Items]
Award vesting rights, percentage												20000.00%
Year five \| RMR LLC \| RMR Inc.
Related Party Transaction [Line Items]
Award vesting rights, percentage												20000.00%