Label	Element	Value
Virtus Herzfeld Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	Virtus Herzfeld Fund (the “Fund”) a series of Virtus Opportunities Trust Supplement dated March 11, 2020 to the Summary Prospectuses and the Virtus Opportunities Trust Statutory Prospectus, each dated January 28, 2020, as supplemented Important Notice to Investors
Risk/Return [Heading]	rr_RiskReturnHeading	Virtus Herzfeld Fund
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	(reflects no deduction for fees, expenses or taxes)
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	The table showing Average Annual Total Returns in the “Performance Information” section of the Fund’s summary prospectus and the summary section of the fund’s statutory prospectus, is hereby replaced in its entirety with the following:
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Investors should retain this supplement with the Prospectuses for future reference.
Virtus Herzfeld Fund \| MSCI All-Country World Index (net) (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	MSCI All-Country World Index (net) (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	26.60%
5 Years	rr_AverageAnnualReturnYear05	8.41%
Since Inception	rr_AverageAnnualReturnSinceInception	10.24%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	8.72%
5 Years	rr_AverageAnnualReturnYear05	3.05%
Since Inception	rr_AverageAnnualReturnSinceInception	2.65%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Herzfeld Composite Benchmark (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Herzfeld Composite Benchmark (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	19.41%
5 Years	rr_AverageAnnualReturnYear05	6.43%
Since Inception	rr_AverageAnnualReturnSinceInception	7.31%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Class A
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	11.45%
5 Years	rr_AverageAnnualReturnYear05	5.18%
Since Inception	rr_AverageAnnualReturnSinceInception	6.37%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Class C
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	17.32%
5 Years	rr_AverageAnnualReturnYear05	5.64%
Since Inception	rr_AverageAnnualReturnSinceInception	6.43%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Class I
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	18.57%
5 Years	rr_AverageAnnualReturnYear05	6.70%
Since Inception	rr_AverageAnnualReturnSinceInception	7.50%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Class I \| After Taxes on Distributions
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	17.17%
5 Years	rr_AverageAnnualReturnYear05	4.79%
Since Inception	rr_AverageAnnualReturnSinceInception	5.64%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012
Virtus Herzfeld Fund \| Class I \| After Taxes on Distributions and Sale of Fund Shares
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	11.13%
5 Years	rr_AverageAnnualReturnYear05	4.53%
Since Inception	rr_AverageAnnualReturnSinceInception	5.22%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 2012

Return Before Taxes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph instructions
-Clause 4

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- Definition

This item represents Average Annual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

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Return Before Taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

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Return Before Taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

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Return Before Taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

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- Definition

The Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". This tag is used when this is reflected in a footnote.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 5

+ Details

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- Definition

If the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also should show the returns of an appropriate broad-based securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____)

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Risk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicated

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A

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