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- Definition

Consent Agreement, Share Price

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- Definition

Amortization of the difference between the carrying amount of the cost method investment and its fair value for the period.

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Represents 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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- Definition

Number Of Affiliates

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- Definition

Officers Compensation, Directors & Officers Liability Insurance Policy Extension Period

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Officers Compensation, Directors & Officers Liability Insurance Policy Premium

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- Definition

Related Party Transaction Property Management Agreement, Payment of Capital Expenditure

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- Definition

Represents the number of shares purchased, from related party.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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

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- Definition

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 - Investment in RMR Inc (Details)		1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 21, 2016 $ / shares	Sep. 30, 2016 USD ($) company	Sep. 30, 2016 USD ($) company $ / shares	Jun. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) company shares	Sep. 30, 2015 USD ($)	Oct. 27, 2016 shares	Oct. 02, 2016 $ / shares shares	Dec. 31, 2015 USD ($)
Related person transactions
Income (loss) recognized arising from equity investments			$ 13,000		$ (24,000)	$ 107,000	$ 70,000
Change in net unrealized gain(loss) on investments			16,562,000		(7,242,000)	$ 56,680,000	(4,407,000)
Officers' compensation, directors' and officers' liability insurance policy extension period		1 year
Officers' compensation, directors' and officers' liability insurance policy premium		$ 142,000
RMR Inc
Related person transactions
Amortization of other liabilities to reduce business and property management fees			$ 943,000		959,000
RMR Inc \| Class A common shares
Related person transactions
Number of shares purchased (in shares) \| shares						2,637,408
Common stock dividend declared (in dollars per share) \| $ / shares			$ 0.25
Five Star
Related person transactions
Payment of capital expenditure			$ 266,000			$ 266,000
AIC
Related person transactions
Equity method investments, carrying value		7,110,000	7,110,000			7,110,000				$ 6,827,000
Income (loss) recognized arising from equity investments			13,000		(24,000)	107,000	70,000
Change in net unrealized gain(loss) on investments			80,000		(72,000)	175,000	(91,000)
Property insurance premium						3,607,000
RMR LLC
Related person transactions
Rental revenue from related party			82,000		$ 51,000	198,000	153,000
RMR Inc \| RMR Inc
Related person transactions
Amortization of other liabilities to reduce business and property management fees						2,829,000	$ 1,202,000
RMR Inc \| RMR LLC
Related person transactions
Initial other liabilities		$ 72,876,000	$ 72,876,000			72,876,000
December 14, 2015 through March 31, 2016 \| RMR Inc \| Class A common shares
Related person transactions
Dividends received				$ 789,000
April 1, 2016 through June 30, 2016 \| RMR Inc \| Class A common shares
Related person transactions
Dividends received						$ 659,000
Subsequent Event
Related person transactions
Common stock dividend declared (in dollars per share) \| $ / shares	$ 0.39
Subsequent Event \| ABP Trust
Related person transactions
Consent agreement, maximum number of shares (in shares) \| shares								18,000,000	10,000,000
Consent agreement, share price (in dollars per share) \| $ / shares									$ 3.00
AIC
Related person transactions
Number of affiliates \| company		7	7			7