XML 54 R42.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Real Estate Dispositions, Held for Sale and Impairment Charges - Components of Income from Real Estate and Related Assets Held for Sale (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Real Estate Properties [Line Items] |  |  |  |
Operating expense | $ 15,172 | $ 13,643 | $ 41,861 | $ 37,995
Real Estate Dispositions [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Operating revenue | 50 | 132 | 271 | 538
Operating expense | 4 | 702 | 193 | 872
Other expense | (10) | (41) | (69) | (155)
Income (loss) from real estate and related assets sold | 36 | (611) | 9 | (489)
Real Estate Held for Sale [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Operating revenue | 362 | 357 | 1,090 | 1,074
Operating expense | 1,918 | 151 | 2,426 | 484
Other expense | (108) | (138) | (338) | (412)
Income (loss) from real estate and related assets sold | $ (1,664) | $ 68 | $ (1,674) | $ 178

X
- Definition Income loss from real estate and related assets held for sale. + References No definition available. + Details
Name: | good_IncomeLossFromRealEstateAndRelatedAssetsHeldForSale
Namespace Prefix: | good_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. + References No definition available. + Details
Name: | us-gaap_OperatingExpenses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. + 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 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
Name: | us-gaap_OtherCostAndExpenseOperating
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | us-gaap_RealEstatePropertiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. + 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) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
Name: | us-gaap_SalesRevenueNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_RealEstatePropertiesAxis=good_RealEstateDispositionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstatePropertiesAxis=good_RealEstateHeldForSaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |