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 November 9, 2023, to the Summary and Statutory Prospectuses for the Fund listed above, each dated January 27, 2023, as supplemented Important Notice to Investors
Risk/Return [Heading]	rr_RiskReturnHeading	Virtus Seix Tax-Exempt Bond Fund
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	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:
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 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 Bloomberg U.S. Aggregate Bond Index, which is the Fund’s broad-based benchmark, measures the U.S. investment grade fixed rate bond market. 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 and SAI for future reference.
Virtus Seix Tax-Exempt Bond Fund \| Bloomberg U.S. Aggregate Bond Index
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	(13.01%)
5 Years	rr_AverageAnnualReturnYear05	0.02%
10 Years	rr_AverageAnnualReturnYear10	1.06%
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	Bloomberg U.S. Aggregate Bond Index
1 Year	rr_AverageAnnualReturnYear01	(6.74%)
5 Years	rr_AverageAnnualReturnYear05	1.39%
10 Years	rr_AverageAnnualReturnYear10	2.05%
Virtus Seix Tax-Exempt Bond Fund \| Class I
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	(7.76%)
5 Years	rr_AverageAnnualReturnYear05	1.00%
10 Years	rr_AverageAnnualReturnYear10	1.67%
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	(7.76%)
5 Years	rr_AverageAnnualReturnYear05	0.91%
10 Years	rr_AverageAnnualReturnYear10	1.61%
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	(3.64%)
5 Years	rr_AverageAnnualReturnYear05	1.38%
10 Years	rr_AverageAnnualReturnYear10	1.92%
Virtus Seix Tax-Exempt Bond Fund \| Class A
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	(10.52%)
5 Years	rr_AverageAnnualReturnYear05	0.18%
10 Years	rr_AverageAnnualReturnYear10	1.13%
Virtus Seix Tax-Exempt Bond Fund \| Class C
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	(8.68%)
5 Years	rr_AverageAnnualReturnYear05	(0.01%)
10 Years	rr_AverageAnnualReturnYear10	0.65%

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

+ Details

Name:	rr_AverageAnnualReturnLabel
Namespace Prefix:	rr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Return Before Taxes.

+ 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 2

+ Details

Name:	rr_AverageAnnualReturnYear01
Namespace Prefix:	rr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Return Before Taxes.

+ 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 2

+ Details

Name:	rr_AverageAnnualReturnYear05
Namespace Prefix:	rr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Return Before Taxes.

+ 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 2

+ Details

Name:	rr_AverageAnnualReturnYear10
Namespace Prefix:	rr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- 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 N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 5

+ Details

Name:	rr_IndexNoDeductionForFeesExpensesTaxes
Namespace Prefix:	rr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Risk/Return Bar Chart and Table.

+ References

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

+ Details

Name:	rr_PerformanceNarrativeTextBlock
Namespace Prefix:	rr_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

- 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 N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii

+ Details

Name:	rr_PerformanceTableClosingTextBlock
Namespace Prefix:	rr_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	rr_RiskReturnAbstract
Namespace Prefix:	rr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ Details

Name:	rr_RiskReturnHeading
Namespace Prefix:	rr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element contains the text of a prospectus supplement (submission type 497) not already contained in an element containing amended text or other data from a previous submission.

+ References

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

+ Details

Name:	rr_SupplementToProspectusTextBlock
Namespace Prefix:	rr_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=cik0001005020_S000055180Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_PerformanceMeasureAxis=cik0001005020_index_Bloomberg_US_Aggregate_Bond_IndexMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_PerformanceMeasureAxis=cik0001005020_index_ICE_BofA_122_Year_US_Municipal_Securities_Index_reflects_no_deduction_for_fees_expenses_or_taxesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_ProspectusShareClassAxis=cik0001005020_C000173506Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_PerformanceMeasureAxis=rr_AfterTaxesOnDistributionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_PerformanceMeasureAxis=rr_AfterTaxesOnDistributionsAndSalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_ProspectusShareClassAxis=cik0001005020_C000173507Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rr_ProspectusShareClassAxis=cik0001005020_C000173508Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: