v3.21.2

Summary of significant accounting policies (Schedule of Changes in Financial Liabilities) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Summary of significant accounting policies |  |  |  |
Balance, beginning | $ 253 | $ 286 | $ 680 |
Change in fair value of warrant derivative liability | (4) | (33) | (394) | $ 150
Change In Financial Liabilities Issuance Of Warrants |  |  |  | 530
Balance, ending | $ 249 | $ 253 | $ 286 | $ 680

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- Definition Change in financial liabilities as result of change in fair value of warrant derivative liability. + References No definition available. + Details
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Namespace Prefix: | sgoc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition Change in financial liabilities as result of issuance of warrants. + References No definition available. + Details
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Namespace Prefix: | sgoc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant