Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5747-111685

+ Details

Name:	us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Investment, Basis Spread on Variable Rate

+ References

No definition available.

+ Details

Name:	vrts_InvestmentBasisSpreadonVariableRate
Namespace Prefix:	vrts_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Investments, Carrying Amount Exceeds Fair Value

+ References

No definition available.

+ Details

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

- Definition

Number of Collateralized Loan Obligations Consolidated

+ References

No definition available.

+ Details

Name:	vrts_NumberofCollateralizedLoanObligationsConsolidated
Namespace Prefix:	vrts_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=vrts_VariableInterestEntityPrimaryBeneficiaryCollateralizedLoanObligationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=vrts_SeniorSecuredFloatingRateNotesNewfleetCLO20161Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=vrts_SubordinatedNotesNewfleetCLO20161Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=vrts_VariableInterestEntityPrimaryBeneficiaryandVotingInterestEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Consolidation - Additional Information (Detail)	12 Months Ended
Consolidation - Additional Information (Detail)	Dec. 31, 2017 USD ($) collateralized_loan_obligation	Dec. 31, 2016 USD ($)
CLOs
Variable Interest Entity [Line Items]
Number of consolidated CLOs \| collateralized_loan_obligation	4
Investments	$ 1,555,879,000	$ 346,967,000
CLOs \| London Interbank Offered Rate (LIBOR)
Variable Interest Entity [Line Items]
Investments, basis spread on variable interest rate	9.50%
CLOs \| London Interbank Offered Rate (LIBOR) \| Minimum
Variable Interest Entity [Line Items]
Basis spread on variable interest rate	1.00%
CLOs \| London Interbank Offered Rate (LIBOR) \| Maximum
Variable Interest Entity [Line Items]
Basis spread on variable interest rate	8.75%
CLOs \| Senior notes
Variable Interest Entity [Line Items]
Unpaid principal balance exceeds fair value	$ 9,700,000
CLOs \| CLO senior secured floating rate notes \| Senior notes
Variable Interest Entity [Line Items]
Debt par value	1,500,000,000.0
CLOs \| CLO subordinated notes
Variable Interest Entity [Line Items]
Debt par value	1,600,000,000.0
CLOs \| CLO subordinated notes \| Subordinated debt
Variable Interest Entity [Line Items]
Debt par value	139,800,000.0
Consolidated investment products
Variable Interest Entity [Line Items]
Investments	1,597,752,000	$ 489,042,000
Fair value, securities, Level 2 to Level 1 transfers, amount	0
Nonconsolidated VIEs
Variable Interest Entity [Line Items]
Carrying value and maximum risk of loss	$ 43,200,000