Related Person Transactions (Details) $ in Thousands					1 Months Ended		3 Months Ended		6 Months Ended			12 Months Ended
	Jul. 23, 2015 USD ($) state room property	Jun. 05, 2015 USD ($) agreement shares	Jun. 04, 2015 shares	Jun. 01, 2015 USD ($) property	Jul. 31, 2015 USD ($) state item property	Jun. 30, 2015 USD ($) property item shares	Jun. 30, 2015 USD ($) property Vote Option item shares	Jun. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) property	Jun. 30, 2015 USD ($) property item shares	Jun. 30, 2014 USD ($) shares	Dec. 31, 2014 USD ($)	Jun. 09, 2015 USD ($)	Apr. 28, 2014 USD ($)	Dec. 31, 2007
Related Party Transaction [Line Items]
Number of management agreements or leases | item						14	14			14
Rental income							$ 69,063	$ 63,736		$ 133,814	$ 127,122
Capital improvements from leased facilities, funded										72,482
Increase (decrease) in minimum annual rent										5,608
Deferred percentage rent revenue							0	698		0	1,572
Adjustments included in rental income necessary to record rent on the straight line basis							1,511	539		2,056	1,106
Proceeds received from the VDOT in connection with the eminent domain taking											6,178
Gain on sale of real estate							11,015	130		11,015	130
Accruals for unpaid amount						$ 42,997	42,997			42,997		$ 40,253
Amount owed for capital expenditure reimbursements						$ 17,698	17,698			17,698		8,658
Earnings (losses) recognized related to equity investments							23	125		$ 95	28
Sonesta ES Suites
Related Party Transaction [Line Items]
Number of hotels to be acquired | property					9
Number of hotel suites | item					1,094
Number of states hotels to be acquired located | state					8
Purchase price excluding closing cost					$ 85,000
Amount expected to be provided for renovation for acquisitions made							$ 45,000
Sonesta agreements
Related Party Transaction [Line Items]
Number of real estate properties leased or managed | property						22	22			22
Management agreement fees and expenses							$ 5,887	4,717		$ 10,401	8,330
Procurement and construction supervision fees							323	1,203		676	1,750
Amount expected to be provided for renovation for acquisitions made										45,000
Payments to acquire building and land														$ 750
Travel Centers of America LLC
Related Party Transaction [Line Items]
Increase (decrease) in minimum annual rent							(3,874)
Gain on sale of real estate							11,015
Aggregate consideration paid							45,042
RMR Inc
Related Party Transaction [Line Items]
Percentage of interest acquired		33.50%
Period prior to acquisition over which weighted average trading prices are calculated		20 days
Preliminary amount of investment acquired		$ 57,817
Amount of investment acquired		55,922
Fair value of investment		129,722
Initial other liabilities		$ 73,800
Investment at carrying value, including transaction costs						$ 132,296	132,296			132,296
Straight line discount amortization period		20 years
Amortization of other liabilities to reduce business and property management fees							231
TA Prior Leases
Related Party Transaction [Line Items]
Amount of percentage rent recognized under the prior agreement and incorporated in the new agreement												2,896
Deferred rent due in December 2022						$ 107,085	$ 107,085			$ 107,085
TA New Leases
Related Party Transaction [Line Items]
Number of renewal options available | Option							2
Term of renewal option							15 years
Percentage of non-fuel revenue over threshold amounts						3.00%	3.00%			3.00%
Increase (decrease) in minimum annual rent							$ 19,597
Number of properties under property management agreement | property						151	151			151
TA No. 1
Related Party Transaction [Line Items]
Deferred rent due in December 2029						$ 27,421	$ 27,421			$ 27,421
TA No. 2
Related Party Transaction [Line Items]
Deferred rent due in December 2028						29,107	29,107			29,107
TA No. 3
Related Party Transaction [Line Items]
Deferred rent due in December 2026						29,324	29,324			29,324
TA No. 4
Related Party Transaction [Line Items]
Deferred rent due in December 2030						$ 21,233	$ 21,233			$ 21,233
TA No. 5
Related Party Transaction [Line Items]
Deferred rent due in June 2024													$ 42,915
Number of properties under property management agreement | property						40	40			40
Class A common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		5,019,121
Travel centers | Travel Centers of America LLC
Related Party Transaction [Line Items]
Number of properties acquired | property							5
Travel centers | TA No. 1
Related Party Transaction [Line Items]
Number of properties leased | property						39	39			39
Minimum rents payable						$ 47,849	$ 47,849			$ 47,849
Travel centers | TA No. 2
Related Party Transaction [Line Items]
Number of properties leased | property						37	37			37
Minimum rents payable						$ 43,192	$ 43,192			$ 43,192
Travel centers | TA No. 3
Related Party Transaction [Line Items]
Number of properties leased | property						38	38			38
Minimum rents payable						$ 48,919	$ 48,919			$ 48,919
Travel centers | TA No. 4
Related Party Transaction [Line Items]
Number of properties leased | property						37	37			37
Minimum rents payable						$ 44,863	$ 44,863			$ 44,863
Hotels | Sonesta ES Suites
Related Party Transaction [Line Items]
Number of properties acquired | property	9
Number of hotel suites | room	1,094
Number of states hotels to be acquired located | state	8
Purchase price excluding closing cost	$ 85,000
Hotels | Sonesta agreements
Related Party Transaction [Line Items]
Fixed minimum return as a percentage of invested capital										8.00%
Hotels | Sonesta agreements | Subsequent event
Related Party Transaction [Line Items]
Number of properties acquired | item					9
Up C Transaction
Related Party Transaction [Line Items]
Indirect economic interest in RMR LLC as a percent		16.20%
Up C Transaction | RMR Trust
Related Party Transaction [Line Items]
Voting power of outstanding capital stock of RMR Inc		91.40%
Direct and indirect economic interest in RMR LLC as a percent		51.60%
Equity conversion ratio of RMR LLC class A membership units							1
Up C Transaction | RMR LLC
Related Party Transaction [Line Items]
Additional consideration needed to cancel RMR Inc. B-2 common stock							$ 0
Up C Transaction | GOV
Related Party Transaction [Line Items]
Indirect economic interest in RMR LLC as a percent		5.00%
Up C Transaction | SIR
Related Party Transaction [Line Items]
Indirect economic interest in RMR LLC as a percent		10.20%
Up C Transaction | SNH
Related Party Transaction [Line Items]
Indirect economic interest in RMR LLC as a percent		17.00%
Up C Transaction | RMR Inc
Related Party Transaction [Line Items]
Equity conversion ratio of RMR Inc. class B-1 common stock							1
Aggregate consideration paid		$ 12,622
Up C Transaction | RMR Inc | RMR Trust
Related Party Transaction [Line Items]
Aggregate consideration paid		11,520
Up C Transaction | RMR Inc | GOV
Related Party Transaction [Line Items]
Aggregate consideration paid		3,917
Up C Transaction | RMR Inc | SIR
Related Party Transaction [Line Items]
Aggregate consideration paid		15,880
Up C Transaction | RMR Inc | SNH
Related Party Transaction [Line Items]
Aggregate consideration paid		$ 13,967
Up C Transaction | Managing Trustees Barry And Adam Portnoy Member | RMR Trust
Related Party Transaction [Line Items]
Period over which shares remain under lock up and registration agreement							10 years
Number of shares under lock up and registration agreement | shares							1,490,000
Up C Transaction | Common shares | RMR Inc
Related Party Transaction [Line Items]
Number of days prior to the acquisition taken into account for valuing at volume weighted average trading prices		20 days
Shares issued in connection with acquisition | shares		1,490,000
Up C Transaction | Common shares | RMR Inc | GOV
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		700,000
Up C Transaction | Common shares | RMR Inc | SIR
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		880,000
Up C Transaction | Common shares | RMR Inc | SNH
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		2,345,000
Up C Transaction | Class A common shares | RMR Inc
Related Party Transaction [Line Items]
Number of votes per equity interest | Vote							1
Shares issued in connection with acquisition | shares		5,019,121
Up C Transaction | Class B1 common shares | RMR Inc
Related Party Transaction [Line Items]
Number of votes per equity interest | Vote							10
Up C Transaction | Class B1 common shares | RMR Inc | RMR Trust
Related Party Transaction [Line Items]
Number of common shares owned | shares		1,000,000
Up C Transaction | Class B2 common shares | RMR Inc
Related Party Transaction [Line Items]
Economic interest in RMR Inc as a percent							0.00%
Number of votes per equity interest | Vote							10
Up C Transaction | Class B2 common shares | RMR Inc | RMR Trust
Related Party Transaction [Line Items]
Number of common shares owned | shares		15,000,000
Up C Transaction | Class A member units | RMR Trust
Related Party Transaction [Line Items]
Business acquisition related party equity interests delivered | shares			30,000,000
Up C Transaction | Class A member units | RMR Inc | RMR Trust
Related Party Transaction [Line Items]
Business acquisition related party equity interests delivered | shares		15,000,000
Up C Transaction | Class B member units | RMR Inc | RMR LLC
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		1,000,000
Travel Centers of America LLC
Related Party Transaction [Line Items]
Percentage of ownership formerly held in subsidiary															100.00%
Common shares of TA held by company as a percent of total TA shares outstanding						8.90%	8.90%			8.90%
Number of properties acquired | property							12
Number of properties where certain assets are leased back to acquiree | property							10
Rental income							$ 1,390	408
Amount of percentage rent recognized							58,836	55,395		$ 115,626	110,678
Minimum rents payable						$ 3,435	3,435	1,863		3,435	1,863
Capital improvements from leased facilities, funded										40,415	21,923
Adjustments included in rental income necessary to record rent on the straight line basis										1,805	$ 845
Accounts receivable from related parties						$ 42,997	$ 42,997			$ 42,997		40,253
Number of common shares owned | shares						3,420,000	3,420,000			3,420,000
Aggregate consideration paid							$ 227,877
Travel Centers of America LLC | Subsequent event
Related Party Transaction [Line Items]
Number of properties acquired | property									2
Number of properties where certain assets are leased back to acquiree | property									1
Aggregate consideration paid									$ 51,506
Travel Centers of America LLC | TA Prior Leases
Related Party Transaction [Line Items]
Number of properties leased | property				144
Number of properties sold | property				5
Travel Centers of America LLC | TA New Leases
Related Party Transaction [Line Items]
Number of properties acquired | property				14
Number of properties where certain assets are leased back to acquiree | property				11
Number of properties acquired and leased back to the acquiree | property				25
Purchase price equal to estimate of development costs, including the cost of land				$ 118,000
Aggregate consideration paid				$ 279,400
Travel Centers of America LLC | TA New Leases | Amended Agreement
Related Party Transaction [Line Items]
Number of management agreements or leases | property				4
Travel Centers of America LLC | TA No. 5
Related Party Transaction [Line Items]
Aggregate amount of percentage rent to be waived						$ 2,500	2,500			$ 2,500
Annual percentage rent waived							$ 2
Travel Centers of America LLC | Travel centers
Related Party Transaction [Line Items]
Number of properties acquired | property				5
Travel Centers of America LLC | Travel centers | TA Prior Leases
Related Party Transaction [Line Items]
Minimum rents payable				$ 45,042
RMR Trust | Up C Transaction | Class B1 common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		1,000,000
RMR Trust | Up C Transaction | Class B2 common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		15,000,000
GOV | Up C Transaction | Class A common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		1,541,201
SNH | Up C Transaction | Class A common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		5,272,787
SIR | Up C Transaction | Class A common shares | RMR Inc
Related Party Transaction [Line Items]
Shares issued in connection with acquisition | shares		3,166,891
RMR LLC
Related Party Transaction [Line Items]
Common shares issued for services rendered by RMR | shares										63,119,000	54,423,000
Base management fee payable monthly in cash (as a percent)						100.00%	100.00%			100.00%
Accrual for RMR LLC employee share grants							$ 647	877		$ 1,383	$ 1,115
Related party reimbursement expenses							29	15
Incentive fees reversed during the period							(205)
Incentive management fee measurement period										2 years
Estimated incentive fees recorded								1,445		$ 8,822	$ 2,296
Shares issued under the business management agreement | shares										63,119,000	54,423,000
Incentive fees payable												$ 0
Business management fees incurred							9,468	10,925		$ 28,464	$ 20,585
RMR LLC | Up C Transaction | Amended Agreement
Related Party Transaction [Line Items]
Termination fee remaining term assumption		10 years
Number of terminated management agreements for a performance reason before termination fee is incurred | agreement		1
Number of RMR LLC terminated management agreements for good cause before termination fee is incurred | agreement		1
Number of terminated management agreements for convenience before termination fee is incurred | agreement		1
Window for providing notice of termination of property management agreement after change of control by the related party		12 months
Window for providing notice of termination of property management agreement for performance by the related party		60 days
Number of business days notice for termination of property management agreement for performance by the related party		60 days
Number of business days notice for termination of property management agreement for convenience by the related party		60 days
RMR LLC | Up C Transaction | Class A member units | RMR Trust
Related Party Transaction [Line Items]
Number of common shares owned | shares		15,000,000
AIC
Related Party Transaction [Line Items]
Combined property insurance policy term						3 years
Property insurance premium						$ 2,656
Terrorism coverage of property insurance						$ 200,000
Terrorism property insurance term						1 year
Coverage of property insurance						$ 500,000
Equity in unrealized (loss) gain of an investee							(64)	23		(19)	41
Earnings (losses) recognized related to equity investments							23	$ 125		95	$ 28
Equity method investments, carrying value						$ 6,910	$ 6,910			$ 6,910