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Represents the acquired lease amortization period.

No definition available.

Name:	gov_AcquiredLeaseAmortizationPeriod
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Period Type:	duration

Common shares owned accounted for as available for sale securities.

No definition available.

Name:	gov_AvailableForSaleSecuritiesCommonSharesOwned
Namespace Prefix:	gov_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

No definition available.

Name:	gov_DeferredCostsLeasingFutureAmortizationExpenseAbstract
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Period Type:	duration

Represents the amount of amortization of deferred leasing costs expected to be recognized after the fifth succeeding fiscal year.

No definition available.

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

Represents the amount of amortization of deferred leasing costs expected to be recognized during year five of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredCostsLeasingFutureAmortizationExpenseYearFive
Namespace Prefix:	gov_
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Represents the amount of amortization of deferred leasing costs expected to be recognized during year four of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredCostsLeasingFutureAmortizationExpenseYearFour
Namespace Prefix:	gov_
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Represents the amount of amortization of deferred leasing costs expected to be recognized during year one of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredCostsLeasingFutureAmortizationExpenseYearOne
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of amortization of deferred leasing costs expected to be recognized during year three of the five succeeding fiscal years.

No definition available.

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

Represents the amount of amortization of deferred leasing costs expected to be recognized during year two of the five succeeding fiscal years.

No definition available.

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

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseAbstract
Namespace Prefix:	gov_
Data Type:	xbrli:stringItemType
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Period Type:	duration

Represents the amount of amortization of deferred financing fees expected to be recognized after the fifth succeeding fiscal year.

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseAfterYearFive
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of amortization of deferred financing fees expected to be recognized during year five of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseYearFive
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of amortization of deferred financing fees expected to be recognized during year four of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseYearFour
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of amortization of deferred financing fees expected to be recognized during year one of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseYearOne
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
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Represents the amount of amortization of deferred financing fees expected to be recognized during year three of the five succeeding fiscal years.

No definition available.

Name:	gov_DeferredFinanceCostsFutureAmortizationExpenseYearThree
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the amount of amortization of deferred financing fees expected to be recognized during year two of the five succeeding fiscal years.

No definition available.

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

Represents the increase or decrease in rental income from amortization of capitalized above market and below market leases.

No definition available.

Name:	gov_IncreaseDecreaseToRentalIncomeFromAmortizationInCapitalizedAboveAndBelowMarketLeases
Namespace Prefix:	gov_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the percentage of ownership in the subsidiary.

No definition available.

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

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.

No definition available.

Name:	gov_SummaryOfSignificantAccountingPoliciesLineItems
Namespace Prefix:	gov_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

For an unclassified balance sheet, the accumulated amortization, as of the reporting date, representing the periodic charge to earnings of deferred costs which are associated with debt obligations existing as of the end of the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Amount of accumulated amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

No definition available.

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Amount of acquired leases acquired as part of a real property acquisition at below market lease rate with a finite life.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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For an unclassified balance sheet, the accumulated amortization, as of the reporting date, which represents the periodic charge to earnings of initial direct costs which have been deferred and are being allocated over the lease term in proportion to the recognition of rental income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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For an unclassified balance sheet, this element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This amount is before considering accumulated amortization representing the periodic charge to earnings to recognize the deferred costs over the term of the related lease.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_DeferredCostsLeasingGross
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Balance Type:	debit
Period Type:	instant

No definition available.

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For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_DeferredFinanceCostsGross
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No definition available.

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable is reduced by allowances attributable to, for instance, credit risk associated with a lessee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_DeferredRentReceivablesNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Name:	us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment
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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

No definition available.

Name:	us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive
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Data Type:	xbrli:monetaryItemType
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.