The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

+ Details

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

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21521-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(5))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

+ Details

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

- Definition

Debt Instrument, Additional Amount Included in Principal from Exercised Options

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentAdditionalAmountIncludedInPrincipalFromExercisedOptions
Namespace Prefix:	vrns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Convertible, Debt Issuance Costs Of Equity Component

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentConvertibleDebtIssuanceCostsOfEquityComponent
Namespace Prefix:	vrns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Convertible, Debt Issuance Costs Of Liability Component

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentConvertibleDebtIssuanceCostsOfLiabilityComponent
Namespace Prefix:	vrns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Convertible, Threshold Consecutive Business Days

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentConvertibleThresholdConsecutiveBusinessDays
Namespace Prefix:	vrns_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Face Amount Excluding Purchasers’ Option

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentFaceAmountExcludingPurchasersOption
Namespace Prefix:	vrns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument Repurchase Price As Percentage of Principal Amount Plus Accrued and Unpaid Interest In Event Of Change

+ References

No definition available.

+ Details

Name:	vrns_DebtInstrumentRepurchasePriceAsPercentageOfPrincipalAmountPlusAccruedAndUnpaidInterestInEventOfChange
Namespace Prefix:	vrns_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Derivative, Initial Cap Price

+ References

No definition available.

+ Details

Name:	vrns_DerivativeInitialCapPrice
Namespace Prefix:	vrns_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Derivative, Percentage Premium Over the Last Reported Sale Price of Company Common Stock

+ References

No definition available.

+ Details

Name:	vrns_DerivativePercentagePremiumOverTheLastReportedSalePriceOfCompanyCommonStock
Namespace Prefix:	vrns_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Payments for Capped Calls

+ References

No definition available.

+ Details

Name:	vrns_PaymentsForCappedCalls
Namespace Prefix:	vrns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Details

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

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AdditionalPaidInCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtConversionByUniqueDescriptionAxis=vrns_DebtConversionOptionOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtConversionByUniqueDescriptionAxis=vrns_DebtConversionOptionTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Convertible Senior Notes and Capped Call Transactions - Narrative (Details)		3 Months Ended	6 Months Ended
	May 11, 2020 USD ($)	Jun. 30, 2021 USD ($) tradingDay $ / shares	Jun. 30, 2021 USD ($) tradingDay $ / shares	Jun. 30, 2020 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of convertible senior notes, net of issuance costs			$ 0	$ 245,308,000
Purchases of capped calls			$ 0	$ 29,348,000
Cap price \| $ / shares		$ 47.24	$ 47.24
Percentage premium over the last reported sale price of company common stock used to calculate cap price			100.00%
2025 Senior Notes
Debt Instrument [Line Items]
Equity component, net of discount and issuance costs		$ 30,794,000	$ 30,794,000
Fair value of the notes		$ 407,935,000	$ 407,935,000
Convertible Debt
Debt Instrument [Line Items]
Purchases of capped calls	$ 29,348,000
Convertible Debt \| 2025 Senior Notes
Debt Instrument [Line Items]
Principal amount excluding purchasers' option	220,000,000
Additional amount included in principal from exercised options	33,000,000
Proceeds from issuance of convertible senior notes, net of issuance costs	$ 245,158,000
Interest rate, stated percentage	1.25%
Debt instrument, convertible, conversion ratio			32.5668
Initial conversion price (in dollars per share) \| $ / shares		$ 30.71	$ 30.71
Repurchase of notes percentage			100.00%
Equity component, net of discount and issuance costs		$ 31,779,000	$ 31,779,000
Interest rate, effective percentage		4.51%	4.51%
Debt issuance costs of liability component		$ 6,857,000	$ 6,857,000
Convertible Debt \| 2025 Senior Notes \| Additional paid-in capital
Debt Instrument [Line Items]
Debt issuance costs of equity component		$ 985,000	$ 985,000
Convertible Debt \| 2025 Senior Notes \| Debt Conversion, Option One
Debt Instrument [Line Items]
Threshold trading days (in trading days) \| tradingDay			20
Threshold consecutive trading days \| tradingDay		30	30
Threshold percentage of conversion price		130.00%	130.00%
Convertible Debt \| 2025 Senior Notes \| Debt Conversion, Option Two
Debt Instrument [Line Items]
Threshold consecutive trading days \| tradingDay			5
Threshold percentage of conversion price			98.00%
Threshold consecutive business days \| tradingDay			5