Label	Element	Value
Virtus Seix Tax-Exempt Bond Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	Virtus Seix Tax-Exempt Bond Fund (the “Fund”), a series of Virtus Opportunities Trust Supplement dated March 22, 2024, to the Summary Prospectus and the Virtus Opportunities Trust Statutory Prospectus pertaining to the Fund, each dated January 29, 2024, as supplemented
Risk/Return [Heading]	rr_RiskReturnHeading	Virtus Seix Tax-Exempt Bond Fund
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	Important Notice to Investors The table showing Average Annual Total Returns and the paragraph immediately after the table in the “Performance Information” section of the Fund’s summary prospectus and the summary section of the statutory prospectus applicable to the Fund, are hereby replaced in their entirety with the following:
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	Effective February 1, 2021, the ICE BofA 1-22 Year U.S. Municipal Securities Index is the Fund’s style-specific benchmark. The ICE BofA 1-22 Year U.S. Municipal Securities Index is a subset of the ICE BofA U.S. Municipal Securities Index including all securities with a remaining term to final maturity less than 22 years, calculated on a total return basis. The indexes are calculated on a total return basis, are unmanaged, and are not available for direct investment.
Performance Table Market Index Changed	rr_PerformanceTableMarketIndexChanged	Effective March 22, 2024, the Fund’s broad-based benchmark is the Bloomberg Municipal Bond Index replacing the Bloomberg U.S. Aggregate Bond Index. The Bloomberg Municipal Bond Index is a market capitalization-weighted index that measures the long-term tax-exempt bond market and is more closely matched to the Fund’s principal investment strategy.
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	(reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Effective March 22, 2024, the Fund’s broad-based benchmark is the Bloomberg Municipal Bond Index replacing the Bloomberg U.S. Aggregate Bond Index. The Bloomberg Municipal Bond Index is a market capitalization-weighted index that measures the long-term tax-exempt bond market and is more closely matched to the Fund’s principal investment strategy. Effective February 1, 2021, the ICE BofA 1-22 Year U.S. Municipal Securities Index is the Fund’s style-specific benchmark. The ICE BofA 1-22 Year U.S. Municipal Securities Index is a subset of the ICE BofA U.S. Municipal Securities Index including all securities with a remaining term to final maturity less than 22 years, calculated on a total return basis. The indexes are calculated on a total return basis, are unmanaged, and are not available for direct investment. Investors should retain this supplement with the Prospectuses for future reference.
Virtus Seix Tax-Exempt Bond Fund \| Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	6.40%
5 Years	rr_AverageAnnualReturnYear05	2.25%
10 Years	rr_AverageAnnualReturnYear10	3.03%
Virtus Seix Tax-Exempt Bond Fund \| Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	5.53%
5 Years	rr_AverageAnnualReturnYear05	1.10%
10 Years	rr_AverageAnnualReturnYear10	1.81%
Virtus Seix Tax-Exempt Bond Fund \| ICE BofA 1-22 Year U.S. Municipal Securities Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	ICE BofA 1-22 Year U.S. Municipal Securities Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	5.65%
5 Years	rr_AverageAnnualReturnYear05	2.24%
10 Years	rr_AverageAnnualReturnYear10	2.77%
Virtus Seix Tax-Exempt Bond Fund \| Class I
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	4.96%
5 Years	rr_AverageAnnualReturnYear05	1.82%
10 Years	rr_AverageAnnualReturnYear10	2.51%
Virtus Seix Tax-Exempt Bond Fund \| Class I \| After Taxes on Distributions
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	4.96%
5 Years	rr_AverageAnnualReturnYear05	1.76%
10 Years	rr_AverageAnnualReturnYear10	2.45%
Virtus Seix Tax-Exempt Bond 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	4.14%
5 Years	rr_AverageAnnualReturnYear05	2.00%
10 Years	rr_AverageAnnualReturnYear10	2.58%
Virtus Seix Tax-Exempt Bond Fund \| Class A
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	1.82%
5 Years	rr_AverageAnnualReturnYear05	1.00%
10 Years	rr_AverageAnnualReturnYear10	1.96%
Virtus Seix Tax-Exempt Bond Fund \| Class C
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	3.92%
5 Years	rr_AverageAnnualReturnYear05	0.80%
10 Years	rr_AverageAnnualReturnYear10	1.48%

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.

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

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Return Before Taxes.

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

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Return Before Taxes.

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

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Return Before Taxes.

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

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+ References

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

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Include the bar chart and table required by paragraphs (b)(2)(ii) and (iii) of this section. Provide a brief explanation of how the information illustrates the variability of the Fund's returns (e.g., by stating that the information provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for 1, 5, and 10 years compare with those of a broad measure of market performance). Provide a statement to the effect that the Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

+ References

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

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Risk/Return Bar Chart and Table.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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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 N-1A
-Section 4
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If the Fund selects an index that is different from the index used in a table for the immediately preceding period, explain the reason(s) for the selection of a different index and provide information for both the newly selected and the former index.

+ References

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

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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 N-1A
-Section 2

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