Government Assistance (Details) $ in Millions	12 Months Ended
Jun. 28, 2025 USD ($)
Public Wireless Supply Chain Innovation Fund Grant
Government Assistance [Line Items]
Government assistance receivables	$ 21.7
Government assistance, transaction duration	3 years
Grant spending	$ 5.8
Public Wireless Supply Chain Innovation Fund Grant \| Software License Fees
Government Assistance [Line Items]
Grant spending	4.0
Public Wireless Supply Chain Innovation Fund Grant \| Management/Administration Fees
Government Assistance [Line Items]
Grant spending	1.8
VALOR Grant
Government Assistance [Line Items]
Government assistance expense	7.1
Government assistance, asset, decrease	1.4
Government assistance, cash reimbursement	10.5
Government assistance receivables	0.6
Other Government Assistance
Government Assistance [Line Items]
Government assistance expense	10.6
Government assistance receivables	$ 17.5
Government Assistance, Expense, Decrease (Increase), Statement of Income or Comprehensive Income [Extensible Enumeration]	Research and development
Government Assistance, Asset, Current, Statement of Financial Position [Extensible Enumeration]	Prepayments and other current assets

Amount of asset from government assistance, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-3

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- Definition

Amount of decrease in asset from government assistance.

+ References

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- Definition

Amount of government assistance awarded that comprises amount received, receivable, and to be received unless condition for government assistance is not met. Includes, but is not limited to, government grant, assistance, incentive, award, subsidy, and loan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-3

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- Definition

Indicates line item in statement of financial position that includes asset from government assistance, classified as current.

+ References

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- Definition

Amount of decrease (increase) in expense from government assistance.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	duration

- Definition

Indicates line item in statement of income or comprehensive income that includes decrease (increase) in expense from government assistance.

+ References

+ Details

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- 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

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- Definition

Duration of government assistance transaction, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-4

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- Definition

Government Assistance, Cash Reimbursement

+ References

No definition available.

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- Definition

Government Assistance, Grant Spending Requirement

+ References

No definition available.

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Namespace Prefix:	viav_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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