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

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Amount Required To Be Prepaid, Percent of Excess Cash Flow

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Annual Principal Payment, Percentage of Principal

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Basis Spread on Variable Rate, Floor

+ References

No definition available.

+ Details

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

- Definition

Debt Instrument, Delayed Draw Fee

+ References

No definition available.

+ Details

Name:	vrts_DebtInstrumentDelayedDrawFee
Namespace Prefix:	vrts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Premium Due If Prepaid In Connection With Repricing Transaction Within Six Months Of Credit Agreement Closing

+ References

No definition available.

+ Details

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

- Definition

Line Of Credit Facility, Potential Additional Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	vrts_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility, Potential Increase In Borrowing Capacity, Pro Forma Leverage Ratio Used For Calculation

+ References

No definition available.

+ Details

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Namespace Prefix:	vrts_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Details

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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_VariableRateAxis=us-gaap_BaseRateMember
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_CreditFacilityAxis=vrts_TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	vrts_LeverageRatioScenarioAxis=vrts_LeverageRatioBelow1.00Member
Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=vrts_SeniorUnsecuredRevolvingCreditFacility2016Member
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Debt (Details)		3 Months Ended	9 Months Ended
Debt (Details)	Jun. 01, 2017 USD ($)	May 31, 2017 USD ($)	Sep. 30, 2017 USD ($)
Credit Facility \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			3.75%
Credit Facility \| Alternate base rate
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			2.75%
Credit Facility \| Minimum \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			3.50%
Credit Facility \| Minimum \| Alternate base rate
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			2.50%
Credit Facility \| Maximum \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			3.75%
Credit Facility \| Maximum \| Alternate base rate
Line of Credit Facility [Line Items]
Basis spread on variable interest rate			2.75%
Credit Facility \| Term loan
Line of Credit Facility [Line Items]
Borrowing capacity	$ 260,000,000.0
Debt term	7 years
Delayed draw fee		$ 1,200,000
Amount outstanding			$ 260,000,000
Annual principal payment, percentage of principal			1.00%
Amount required to be prepaid, percentage of excess cash flow			50.00%
Premium due in connection with a prepayment in connection with a repricing transaction within the six-month period following the closing of the Credit Agreement			1.00%
Credit Facility \| Term loan \| Leverage ratio below 1.00 to 1.00
Line of Credit Facility [Line Items]
Amount required to be prepaid, percentage of excess cash flow			25.00%
Credit Facility \| Term loan \| Leverage ratio below 0.50 to 1.00
Line of Credit Facility [Line Items]
Amount required to be prepaid, percentage of excess cash flow			0.00%
Credit Facility \| Term loan \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable interest rate, floor			0.75%
Credit Facility \| Revolving credit facility
Line of Credit Facility [Line Items]
Borrowing capacity	$ 100,000,000.0
Debt term	5 years
Amount outstanding			$ 0
Potential additional borrowing capacity	$ 75,000,000.0
Pro forma leverage ratio used for calculation of potential increase in borrowing capacity	1.75
Commitment fee percentage			0.50%
Credit Facility \| Revolving credit facility \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable interest rate, floor			0.00%
Credit Facility \| Revolving credit facility \| Minimum
Line of Credit Facility [Line Items]
Commitment fee percentage			0.375%
Credit Facility \| Revolving credit facility \| Maximum
Line of Credit Facility [Line Items]
Commitment fee percentage			0.50%
Previous Credit Facility \| Revolving credit facility
Line of Credit Facility [Line Items]
Write off of unamortized deferred financing costs			$ 1,100,000