Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Assets
Cash equivalents	$ 135,115,000	$ 158,596,000
Investment securities - fair value
Fair Value	53,351,000	59,271,000
Investment securities - available for sale	0	2,023,000
Total assets measured at fair value	196,318,000	226,606,000
Sponsored funds
Investment securities - fair value
Fair Value	34,127,000	40,191,000
Equity securities
Investment securities - fair value
Fair Value	19,213,000	16,981,000
Debt securities
Investment securities - fair value
Fair Value	11,000	2,099,000
Collateralized loan obligation
Investment securities - fair value
Investment securities - available for sale		2,023,000
Nonqualified retirement plan assets
Investment securities - fair value
Nonqualified retirement plan assets	7,852,000	6,716,000
Level 1
Assets
Cash equivalents	135,115,000	158,596,000
Investment securities - fair value
Total assets measured at fair value	196,307,000	222,484,000
Level 1 \| Sponsored funds
Investment securities - fair value
Fair Value	34,127,000	40,191,000
Level 1 \| Equity securities
Investment securities - fair value
Fair Value	19,213,000	16,981,000
Level 1 \| Debt securities
Investment securities - fair value
Fair Value	0	0
Level 1 \| Collateralized loan obligation
Investment securities - fair value
Investment securities - available for sale		0
Level 1 \| Nonqualified retirement plan assets
Investment securities - fair value
Nonqualified retirement plan assets	7,852,000	6,716,000
Level 2
Assets
Cash equivalents	0	0
Investment securities - fair value
Total assets measured at fair value	11,000	0
Level 2 \| Sponsored funds
Investment securities - fair value
Fair Value	0	0
Level 2 \| Equity securities
Investment securities - fair value
Fair Value	0	0
Level 2 \| Debt securities
Investment securities - fair value
Fair Value	11,000	0
Level 2 \| Collateralized loan obligation
Investment securities - fair value
Investment securities - available for sale		0
Level 2 \| Nonqualified retirement plan assets
Investment securities - fair value
Nonqualified retirement plan assets	0	0
Level 3
Assets
Cash equivalents	0	0
Investment securities - fair value
Total assets measured at fair value	0	4,122,000
Level 3 \| Sponsored funds
Investment securities - fair value
Fair Value	0	0
Level 3 \| Equity securities
Investment securities - fair value
Fair Value	0	0
Level 3 \| Debt securities
Investment securities - fair value
Fair Value	0	2,099,000
Level 3 \| Collateralized loan obligation
Investment securities - fair value
Investment securities - available for sale		2,023,000
Level 3 \| Nonqualified retirement plan assets
Investment securities - fair value
Nonqualified retirement plan assets	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_AssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_AssetsFairValueDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

+ Details

Name:	us-gaap_CashAndCashEquivalentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_MarketableSecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Investments In Nonqualified Retirement Plan Assets

+ References

No definition available.

+ Details

Name:	vrts_InvestmentsInNonqualifiedRetirementPlanAssets
Namespace Prefix:	vrts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancialInstrumentAxis=vrts_SponsoredFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=vrts_TradingDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CollateralizedDebtObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=vrts_NonqualifiedRetirementPlanAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: