Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Sep. 30, 2020
Registrant Name	Virtus Opportunities Trust
Entity Central Index Key	0001005020
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Sep. 24, 2021
Document Effective Date	Sep. 24, 2021
Prospectus Date	Sep. 24, 2021
Virtus KAR International Small-Mid Cap Fund \| Class A
Prospectus:
Trading Symbol	VISAX
Virtus KAR International Small-Mid Cap Fund \| Class C
Prospectus:
Trading Symbol	VCISX
Virtus KAR International Small-Mid Cap Fund \| Class I
Prospectus:
Trading Symbol	VIISX
Virtus KAR International Small-Mid Cap Fund \| Class R6
Prospectus:
Trading Symbol	VRISX

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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