Represents the expense amount accrued for employee share grants to RMR LLC employees.

No definition available.

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- Definition

Represents the number of anniversary during which restrcited shares vest.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Total expense amount to reimburse a related party.

+ References

No definition available.

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- Definition

Represents the amount of amortization of the liability recorded during the period.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the construction supervision fees as a percentage of construction costs pursuant to property management agreement with related parties.

+ References

No definition available.

+ Details

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Namespace Prefix:	gov_
Data Type:	num:percentItemType
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- Definition

Represents the incentive fee payable in a related party transaction.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Represents the property management and construction supervision fees incurred pursuant to business and property management agreements with related parties.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the property management fees as a percentage of gross collected rents pursuant to property management agreement with related parties.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Represents the aggregate market value at grant date for nonvested equity-based awards during the period on other than stock (or unit) options plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the portion of restricted shares which will vest on the grant date.

+ References

No definition available.

+ Details

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Namespace Prefix:	gov_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Represents the portion of awards granted which will vest on each of the next four anniversaries of the grant date.

+ References

No definition available.

+ Details

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Namespace Prefix:	gov_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Related Parties
-URI http://asc.fasb.org/extlink&oid=16382449

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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Related Party Transactions - RMR LLC Management Fees and Reimbursements (Details) $ in Thousands		1 Months Ended		5 Months Ended	12 Months Ended
	Sep. 24, 2015 shares	Sep. 30, 2015 shares	Mar. 31, 2013 shares	Jun. 05, 2015 shares	Dec. 31, 2015 USD ($) item shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) shares
Related Party Transaction
Number of shares issued \| shares					23,222
Shares purchased from certain of our officers and other employees of RMR LLC \| shares	10,721
EQC
Related Party Transaction
Percentage of ownership interest					100.00%
RMR LLC
Related Party Transaction
Business management fees					$ 9,934	$ 10,226	$ 9,341
Recognized amortization of the liability					372
Number of shares issued \| shares			20,230	19,339		42,442
Incentive fees payable					$ 0	$ 0	0
Property management fees as a percentage of gross collected rents					3.00%
Construction supervision fees as a percentage of construction costs					5.00%
Property management and construction supervision fees					$ 7,977	8,203	7,877
Related party reimbursement expenses					$ 9,641	$ 7,982	$ 6,822
Number of shares granted to each trustee under the award plan \| shares					53,100	51,150	48,350
Aggregate market value of shares awarded					$ 841	$ 1,191	$ 1,142
Vesting rights percentage for restricted shares vesting on the grant date					0.20%
Vesting rights percentage for restricted shares vesting on each of the next four anniversaries of the grant date					0.20%
Number of vesting anniversary \| item					4
Shares purchased from certain of our officers and other employees of RMR LLC \| shares		10,721
Accrual for RMR LLC employee share grants					$ 937	1,287	1,165
Rental income earned					$ 341	$ 61	$ 31