Liquidity - (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended	6 Months Ended
Jul. 31, 2013 Subsequent Event [Member]	Dec. 31, 2014 Subsequent Event [Member]	Jun. 30, 2014 Guadalupe de los Reyes gold/silver project [Member]
Cash Burn Rate Per Quarter		$ 2,000
Anticipation sale amount to be receive subject to purchase option	$ 6,000		$ 850

Anticipation sale amount to be receive subject to purchase option

No definition available.

Name:	vgz_AnticipationSaleAmountToBeReceiveSubjectToPurchaseOption
Namespace Prefix:	vgz_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration