Debt	12 Months Ended
Dec. 31, 2014
Debt Disclosure [Abstract]
Debt Disclosure [Text Block]	8. Debt During March 2013, the Company entered into a credit agreement with Sprott Resources Lending Partnership (the “Lender”) for purposes of establishing a C$10,000 loan facility (the “2013 Facility”) ($9,637 proceeds net of transaction costs). The 2013 Facility bore an interest rate of 8% per annum, payable monthly and originally matured March 2014, with early repayment of the 2013 Facility allowed, at the Company’s option, provided that at least four months interest had been paid. In September 2013, the Company and the Lender agreed to extend the maturity date of the 2013 Facility to March 2015. In addition to interest, the 2013 Facility provided the Lender total fees of 3.5% of the 2013 Facility amount, including C$100 ($99) in cash and the issuance of 125,798 Vista common shares. As consideration for the extended maturity date, we paid the Lender an extension fee comprised of 486,382 Vista common shares. The 2013 Facility was secured by a general security agreement with certain exclusions. As additional security, the Company pledged all the Company’s Midas Gold Shares (Note 4). During October 2013, in accordance with the terms of the 2013 Facility, the Company repaid approximately $2,960 towards the 2013 Facility principal outstanding using proceeds from the Los Cardones sale (Note 5). During February 2014, in accordance with the terms of the 2013 Facility, the Company repaid approximately $5,000 towards the 2013 Facility principal then outstanding using proceeds from the sale of Midas Gold Shares (Note 4). During March 2014, we repaid the outstanding principal balance of $1,344 in full.

Debt

12 Months Ended

Dec. 31, 2014

8. Debt

During March 2013, the Company entered into a credit agreement with Sprott Resources Lending Partnership (the “Lender”) for purposes of establishing a C$10,000 loan facility (the “2013 Facility”) ($9,637 proceeds net of transaction costs). The 2013 Facility bore an interest rate of 8% per annum, payable monthly and originally matured March 2014, with early repayment of the 2013 Facility allowed, at the Company’s option, provided that at least four months interest had been paid. In September 2013, the Company and the Lender agreed to extend the maturity date of the 2013 Facility to March 2015.

In addition to interest, the 2013 Facility provided the Lender total fees of 3.5% of the 2013 Facility amount, including C$100 ($99) in cash and the issuance of 125,798 Vista common shares. As consideration for the extended maturity date, we paid the Lender an extension fee comprised of 486,382 Vista common shares.

The 2013 Facility was secured by a general security agreement with certain exclusions. As additional security, the Company pledged all the Company’s Midas Gold Shares (Note 4).

During October 2013, in accordance with the terms of the 2013 Facility, the Company repaid approximately $2,960 towards the 2013 Facility principal outstanding using proceeds from the Los Cardones sale (Note 5).

During February 2014, in accordance with the terms of the 2013 Facility, the Company repaid approximately $5,000 towards the 2013 Facility principal then outstanding using proceeds from the sale of Midas Gold Shares (Note 4). During March 2014, we repaid the outstanding principal balance of $1,344 in full.