Related Person Transactions - RMR LLC Management Fees and Reimbursements (Details) - RMR LLC - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Related Person Transaction
Business management fees	$ 2,508	$ 2,561
Number of shares issued		11,157
Incentive fees payable	0	$ 0
Property management and construction supervision fees	2,109	2,016
Related party reimbursement expenses	2,944	2,510
Accrual for RMR LLC employee share grants and internal audit services	234	314
Rental income earned	$ 91	$ 15
Percentage of ownership interest	27.90%

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

No definition available.

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Period Type:	duration

- Definition

Total expense amount to reimburse a related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the incentive fee payable in a related party transaction.

+ References

No definition available.

+ Details

Name:	gov_RelatedPartyTransactionIncentiveFeePayable
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Name:	gov_RelatedPartyTransactionPropertyManagementAndConstructionSupervisionFees
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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Data Type:	num:percentItemType
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Period Type:	instant

- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Related Parties
-URI http://asc.fasb.org/extlink&oid=16382449

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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
Balance Type:	na
Period Type:	duration

- Details

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