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

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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Namespace Prefix:	us-gaap_
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://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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
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 the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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

- 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

Additional Loan Facility Maximum Commitment Amount

+ References

No definition available.

+ Details

Name:	var_AdditionalLoanFacilityMaximumCommitmentAmount
Namespace Prefix:	var_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Contract Repayment Date

+ References

No definition available.

+ Details

Name:	var_DebtInstrumentContractRepaymentDate
Namespace Prefix:	var_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage added to Eurodollar base rate before margin.

+ References

No definition available.

+ Details

Name:	var_PercentageAddedToEurodollarBaseRateBeforeMargin
Namespace Prefix:	var_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_EurodollarMember
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Data Type:	na
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- Details

Name:	us-gaap_VariableRateAxis=var_EurodollarPlus1Member
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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix:
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- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=var_SwingLineLoansMember
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BORROWINGS - Additional Information (Detail)		3 Months Ended
BORROWINGS - Additional Information (Detail)	Nov. 01, 2019 USD ($)	Jan. 03, 2020 JPY (¥)	Oct. 31, 2019 USD ($)
Revolving Credit Facility
Line Of Credit Facility [Line Items]
Credit facility term (in years)	5 years
Loan facility, maximum borrowing capacity	$ 1,200,000,000		$ 1,800,000,000
Additional maximum commitment amount	100,000,000.0
Revolving Credit Facility \| Minimum
Line Of Credit Facility [Line Items]
Commitment fee		0.10%
Revolving Credit Facility \| Maximum
Line Of Credit Facility [Line Items]
Commitment fee		0.225%
Eurodollar \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Debt instrument, contract repayment date		12 months
Eurodollar \| Revolving Credit Facility \| Minimum
Line Of Credit Facility [Line Items]
Line of credit, basis spread on variable rate (as a percent)		1.00%
Eurodollar \| Revolving Credit Facility \| Maximum
Line Of Credit Facility [Line Items]
Line of credit, basis spread on variable rate (as a percent)		1.375%
Eurodollar Rate plus 1% \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Percentage added to Eurodollar base rate before margin (as a percent)		1.00%
Eurodollar Rate plus 1% \| Revolving Credit Facility \| Minimum
Line Of Credit Facility [Line Items]
Line of credit, basis spread on variable rate (as a percent)		0.00%
Eurodollar Rate plus 1% \| Revolving Credit Facility \| Maximum
Line Of Credit Facility [Line Items]
Line of credit, basis spread on variable rate (as a percent)		0.375%
Federal Funds Rate \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Line of credit, basis spread on variable rate (as a percent)		0.50%
Sumitomo Credit Facility
Line Of Credit Facility [Line Items]
Loan facility, maximum borrowing capacity \| ¥		¥ 3,000,000,000.0
Outstanding principal balance \| ¥		¥ 0
Line of credit, basis spread on variable rate (as a percent)		0.50%
Multi-currency Borrowings \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Loan facility, maximum borrowing capacity	500,000,000
Letter of Credit \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Loan facility, maximum borrowing capacity	225,000,000		$ 50,000,000.0
Swing Line Loans \| Revolving Credit Facility
Line Of Credit Facility [Line Items]
Loan facility, maximum borrowing capacity	$ 25,000,000