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Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Jun. 28, 2024 | Jun. 30, 2023 | Jul. 01, 2022 | Dec. 31, 2021 | Dec. 27, 2024
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Net funded (unfunded) status | $ (6) |  |  |  | $ (7)
The Flash Business of Western Digital Corporation [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Net funded (unfunded) status | (6) | $ (5) |  |  |
Defined contribution plan employer matching contribution percent of match |  |  |  | 50.00% |
Defined contribution plan employers matching contribution annual vesting percentage |  |  |  | 6.00% |
Defined contribution plan, cost | $ 5 | $ 9 | $ 15 |  |
The Flash Business of Western Digital Corporation [Member] | Combined Pre Tax And Roth Basis [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Defined contribution plan, maximum Annual contributions per employee, percent |  |  |  | 75.00% |
The Flash Business of Western Digital Corporation [Member] | Combined Pre Tax Catch Up And Roth Catch Up Basis [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Defined contribution plan, maximum Annual contributions per employee, percent |  |  |  | 10.00% |
The Flash Business of Western Digital Corporation [Member] | Non Roth After Tax Basis [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Defined contribution plan, maximum Annual contributions per employee, percent |  |  |  | 10.00% |
The Flash Business of Western Digital Corporation [Member] | Combined Pre Tax And Roth Basis Regardless Of Age [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Defined contribution plan, maximum Annual contributions per employee, percent |  |  |  | 85.00% |
The Flash Business of Western Digital Corporation [Member] | After Tax Basis [Member] |  |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |  |
Defined contribution plan, maximum Annual contributions per employee, percent |  |  |  | 10.00% |

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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 70 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480794/715-70-50-1 + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 70 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480794/715-70-50-1 + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Details
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