Net Income (Loss) per Common Share - Narrative (Details) - $ / shares shares in Millions	Apr. 03, 2026	Jun. 27, 2025	Feb. 21, 2025
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Shares issued (in shares)	148	146	145
Par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Western Digital Corporation
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Percent distribution of shares			80.10%

Spin-Off Transaction, Pro Rata Distribution, Outstanding Shares Percentage

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- Definition

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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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
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