Subsequent Events	6 Months Ended
Jun. 30, 2021
Subsequent Events
Subsequent Events	11. Subsequent Event On July 12, 2021, Vista closed a public offering of 12,272,730 units of the Company (the “Units), at a price of $1.10 per Unit, for aggregate gross proceeds of approximately $13,500, prior to deductions for underwriting discounts, commissions and other costs. Each Unit consisted of one Common Share and one-half of one Common Share purchase warrant (each whole warrant, a “Warrant”). Each Warrant is exercisable from the date of issuance for thirty-six months and entitles the holder thereof to purchase one Common Share upon exercise at an exercise price of $1.25 per Common Share. In addition, the underwriter partially exercised its option to purchase an additional 920,454 Warrants. We also issued 351,282 underwriter warrants to the underwriters in the offering, with terms identical to the Warrants.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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