XML 54 R39.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Real Estate and Intangible Assets - Pro-Forma Condensed Consolidated Statements of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating Data: |  |  |  |  |  |  |  |  |  |  |
Total operating revenue |  |  |  |  |  |  |  |  |  | $ 88,304 | $ 89,720
Total operating expenses |  |  |  |  |  |  |  |  |  | (56,697) | (54,480)
Other expenses, net |  |  |  |  |  |  |  |  |  | (27,429) | (31,014)
Net income |  |  |  |  |  |  |  |  |  | 4,178 | 4,226
Dividends attributable to preferred and senior common stock | $ (2,802) | $ (2,767) | $ (2,686) | $ (2,621) | $ (2,607) | $ (2,256) | $ (1,514) | $ (1,279) |  | (7,656) | (5,101)
Net loss attributable to common stockholders |  |  |  |  |  |  |  |  |  | $ (3,478) | $ (875)
Share and Per Share Data: |  |  |  |  |  |  |  |  |  |  |
Basic and diluted loss per share of common stock - pro forma (in dollars per share) |  |  |  |  |  |  |  |  |  | $ (0.15) | $ (0.04)
Loss attributable to common shareholders (in dollars per share) | $ (0.17) | $ (0.01) | $ (0.08) | $ 0.07 | $ (0.01) | $ (0.10) | $ (0.03) | $ (0.02) | $ (0.19) | $ (0.16) | $ (0.07)
Weighted average shares outstanding-basic and diluted (in shares) |  |  |  |  |  |  |  |  | 26,358,237 | 23,193,962 | 21,159,597

X
- Definition Business acquisition pro forma dividends attributable to preferred and senior common stock. + References No definition available. + Details
Name: | good_BusinessAcquisitionProFormaDividendsAttributableToPreferredAndSeniorCommonStock
Namespace Prefix: | good_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Business acquisition proforma earnings per share basic and diluted. + References No definition available. + Details
Name: | good_BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted
Namespace Prefix: | good_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Business acquisition pro forma net income. + References No definition available. + Details
Name: | good_BusinessAcquisitionProFormaNetIncome
Namespace Prefix: | good_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Business acquisition pro forma operating expenses. + References No definition available. + Details
Name: | good_BusinessAcquisitionProFormaOperatingExpenses
Namespace Prefix: | good_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Business acquisition pro forma other expenses. + References No definition available. + Details
Name: | good_BusinessAcquisitionProFormaOtherExpenses
Namespace Prefix: | good_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Operating data. + References No definition available. + Details
Name: | good_OperatingDataAbstract
Namespace Prefix: | good_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share and per share data. + References No definition available. + Details
Name: | good_ShareAndPerShareDataAbstract
Namespace Prefix: | good_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionsProFormaRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References No definition available. + Details
Name: | us-gaap_EarningsPerShareBasicAndDiluted
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS). + References No definition available. + Details
Name: | us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration