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.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of cost for defined contribution plan.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Section 50
-Paragraph 1
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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.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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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%