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v3.20.4

Significant Accounting Policies (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Significant Accounting Policies |  |
Minimum period for maturity dates for short-term investments | 90 days | 90 days

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- References No definition available. + Details
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- Definition Minimum period for maturity dates relating to short-term investments, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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Namespace Prefix: | vgz_
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