Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Cash equivalents	$ 73,434	$ 48,620
Other investments:
Total assets measured at fair value	154,901	129,335
Sponsored funds
Marketable securities trading:
Marketable securities trading	55,660	60,019
Equity securities
Marketable securities trading:
Marketable securities trading	12,740	11,473
Sponsored closed-end funds
Marketable securities available-for-sale:
Marketable securities available-for-sale	3,762	3,415
Collateralized loan obligation
Other investments:
Investment in collateralized loan obligation	2,909
Nonqualified retirement plan assets
Other investments:
Nonqualified retirement plan assets	6,396	5,808
Level 1
Assets
Cash equivalents	73,434	48,620
Other investments:
Total assets measured at fair value	151,992	129,335
Level 1 \| Sponsored funds
Marketable securities trading:
Marketable securities trading	55,660	60,019
Level 1 \| Equity securities
Marketable securities trading:
Marketable securities trading	12,740	11,473
Level 1 \| Sponsored closed-end funds
Marketable securities available-for-sale:
Marketable securities available-for-sale	3,762	3,415
Level 1 \| Collateralized loan obligation
Other investments:
Investment in collateralized loan obligation	0
Level 1 \| Nonqualified retirement plan assets
Other investments:
Nonqualified retirement plan assets	6,396	5,808
Level 2
Assets
Cash equivalents	0	0
Other investments:
Total assets measured at fair value	0	0
Level 2 \| Sponsored funds
Marketable securities trading:
Marketable securities trading	0	0
Level 2 \| Equity securities
Marketable securities trading:
Marketable securities trading	0	0
Level 2 \| Sponsored closed-end funds
Marketable securities available-for-sale:
Marketable securities available-for-sale	0	0
Level 2 \| Collateralized loan obligation
Other investments:
Investment in collateralized loan obligation	0
Level 2 \| Nonqualified retirement plan assets
Other investments:
Nonqualified retirement plan assets	0	0
Level 3
Assets
Cash equivalents	0	0
Other investments:
Total assets measured at fair value	2,909	0
Level 3 \| Sponsored funds
Marketable securities trading:
Marketable securities trading	0	0
Level 3 \| Equity securities
Marketable securities trading:
Marketable securities trading	0	0
Level 3 \| Sponsored closed-end funds
Marketable securities available-for-sale:
Marketable securities available-for-sale	0	0
Level 3 \| Collateralized loan obligation
Other investments:
Investment in collateralized loan obligation	2,909
Level 3 \| Nonqualified retirement plan assets
Other investments:
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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&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 and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

+ Details

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

- References

No definition available.

+ Details

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

- 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

- References

No definition available.

+ Details

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

- Definition

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Investments In Collateralized Loan Obligations

+ References

No definition available.

+ Details

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

- 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_MajorTypesOfDebtAndEquitySecuritiesAxis=vrts_SponsoredFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=vrts_SponsoredClosedEndFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=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: