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

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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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Aggregate additional coverage amount of combined directors' and officers' liability insurance policy, purchased by the related party.

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No definition available.

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Aggregate coverage amount of combined directors' and officers' liability insurance policy, purchased by the related party.

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Aggregate additional coverage amount of combined directors' and officers' liability insurance policy, purchased by the related party.

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No definition available.

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This element represents the number of properties acquired or agreed to be acquired by the entity during the period.

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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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Represents the insurance coverage of the property insurance purchased from related parties.

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Represents the insurance coverage of the property insurance on a large property purchased from related parties.

+ References

No definition available.

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Represents insurance coverage for terrorism of the property insurance purchased from related parties.

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No definition available.

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Area of a real estate property.

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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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The number of states the entity operates in as of the balance sheet date.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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A contract to provide coverage or protection in exchange for a payment or "premium". Examples of insurance protection include liability and property insurance. The entity paying the premiums for the protection will have insurance expense and possibly an asset, Prepaid Insurance (if the premiums are paid in advance).

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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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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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Related Person Transactions - Leases with RMR LLC (Details) $ in Thousands		1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 29, 2015 USD ($) ft² state property	Jun. 30, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jan. 31, 2015 USD ($) ft² property	Sep. 30, 2015 USD ($) ft² item	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) ft² property item	Sep. 30, 2014 USD ($)	Dec. 31, 2014 property
Related person transactions
Number of states in which properties are located \| item					43		43
Income (loss) recognized arising from equity investments					$ (24)	$ 38	$ 70	$ 59
Change in net unrealized (loss) gain on investments					$ (7,242)	(5,404)	(4,407)	(6,684)
RMR LLC
Related person transactions
Rental revenue from related party							$ 153
Acquisition
Related person transactions
Number of properties acquired or agreed to be acquired \| property							23
Acquisition \| MOBs
Related person transactions
Number of properties acquired or agreed to be acquired \| property				23			23		2
Purchase price excluding closing costs and working capital adjustments				$ 531,623			$ 531,623
Area of real estate properties (in square feet) \| ft²				2,170,000	2,170,000		2,170,000
Acquisition \| MOBs \| SIR
Related person transactions
Amount from SIR related to working capital activity			$ 8,993
SIR
Related person transactions
Debt disposed of from properties sold	$ 29,955
SIR \| Acquisition \| MOBs
Related person transactions
Number of properties acquired or agreed to be acquired \| property	23
Purchase price excluding closing costs and working capital adjustments	$ 539,000
Area of real estate properties (in square feet) \| ft²	2,170,000
Number of states in which properties are located \| state	12
AIC
Related person transactions
Equity method investments, carrying value					$ 6,807		$ 6,807
Income (loss) recognized arising from equity investments					(24)	59	70	38
Change in net unrealized (loss) gain on investments					(72)	$ (33)	(91)	$ 17
Coverage of purchased property insurance		$ 500,000
Coverage of purchased property insurance for large property		1,000,000
Coverage of purchased property terror insurance		200,000
Property insurance premium		$ 4,222
RMR LLC
Related person transactions
Aggregate coverage of combined directors' and officers' liability insurance policy purchased by the related party					10,000		10,000
Aggregate additional coverage of combined directors' and officers' liability insurance policy purchased by the related party					20,000		20,000
Non-indemnifiable coverage of combined directors' and officers' liability insurance policy purchased by the related party							5,000
Premium payable for combined directors' and officers' liability insurance policy					$ 502		$ 502