v2.4.1.9
Warrant derivative liability (Public warrants) (Details) (Public Warrants [Member], USD $)
In Thousands, except Share data, unless otherwise specified
1 Months Ended 12 Months Ended
Mar. 31, 2008
Dec. 31, 2011
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Public Warrants [Member]
         
Warrant Activity [Line Items]          
Public Offering units sold 4,239,300sgoc_PublicOfferingUnitsSold
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
       
Per unit selling price $ 8.00us-gaap_EquityIssuancePerShareAmount
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
       
Warrants outstanding 4,239,300us-gaap_ClassOfWarrantOrRightOutstanding
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     598,850us-gaap_ClassOfWarrantOrRightOutstanding
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
598,850us-gaap_ClassOfWarrantOrRightOutstanding
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
Warrants redeemed 2,673,273sgoc_WarrantsRedeemed
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
       
Warrant redemption price per share $ 0.50sgoc_WarrantRedemptionPricePerShare
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
       
Warrants repurchased   967,177sgoc_WarrantsRepurchased
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     
Warrants repurchased, value   $ 361sgoc_WarrantsRepurchasedValue
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     
Warrants repurchased, average price per share   $ 0.37sgoc_WarrantsRepurchasedAveragePricePerShare
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     
Warrant, cap price   11.50us-gaap_DerivativeCapPrice
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     
Warrant exercise price per share, after price cap exceeded   $ 0.01sgoc_WarrantExercisePricePerShareAfterCapPriceExceeded
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
     
Market price per share       $ 0.02sgoc_QuotedMarketPricePerShare
/ us-gaap_ClassOfWarrantOrRightAxis
= sgoc_PublicWarrantsMember
 
Expiration date   Mar. 07, 2014