v3.26.1
Related Parties and Related Commitments and Contingencies - Additional Information (Details)
3 Months Ended 12 Months Ended
Jan. 06, 2025
USD ($)
Oct. 01, 2024
USD ($)
Sep. 29, 2024
USD ($)
Sep. 28, 2024
USD ($)
installment
Jul. 03, 2026
USD ($)
Jul. 03, 2026
USD ($)
Jun. 27, 2025
USD ($)
Jun. 28, 2024
USD ($)
Jan. 29, 2026
USD ($)
Feb. 21, 2025
USD ($)
Related Party Transaction [Line Items]                    
Distributions from Flash Ventures           $ 0 $ 176,000,000 $ 0    
(Gain) loss on business divestiture       $ 34,000,000   (10,000,000) 34,000,000 0    
Proceeds from dispositions of business           25,000,000 401,000,000 0    
Net transfers from (to) Western Digital Corporation per Consolidated Statements of Shareholders’ Equity             (612,000,000) 275,000,000    
Tax indemnification liability         $ 128,000,000 128,000,000 110,000,000      
Repayments of debt           $ 1,900,000,000 $ 100,000,000 0    
Accounts Receivable | Customer Concentration Risk | Unis Venture                    
Related Party Transaction [Line Items]                    
Concentration risk, percentage           1.00% 1.00%      
SanDisk Semiconductor (Shanghai) Co. Ltd.                    
Related Party Transaction [Line Items]                    
Commitment term     5 years              
Purchase commitment amount     $ 550,000,000              
Renewal term           1 year        
SanDisk Semiconductor (Shanghai) Co. Ltd. | Certain Flash-Based Products                    
Related Party Transaction [Line Items]                    
Commitment purchases           $ 519,000,000 $ 341,000,000      
Accounts payable         143,000,000 143,000,000 121,000,000      
Disposed of by sale | SanDisk Semiconductor (Shanghai) Co. Ltd.                    
Related Party Transaction [Line Items]                    
Ownership percentage sold       80.00%            
(Gain) loss on business divestiture         10,000,000          
Cash and cash equivalents       $ (71,000,000)            
Goodwill       382,000,000            
Disposal consideration       $ 659,000,000            
Proceeds from dispositions of business $ 210,000,000 $ 262,000,000       187,000,000        
Number of installment payments | installment       5            
Installment payment       $ 37,000,000   27,000,000        
Consideration receivable         139,000,000 139,000,000 168,000,000      
Present value discount         12,000,000 $ 12,000,000        
Effective interest method, term           5 years        
Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent | Disposed of by sale | SanDisk Semiconductor (Shanghai) Co. Ltd.                    
Related Party Transaction [Line Items]                    
Consideration receivable         37,000,000 $ 37,000,000 37,000,000      
Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent | Disposed of by sale | SanDisk Semiconductor (Shanghai) Co. Ltd.                    
Related Party Transaction [Line Items]                    
Consideration receivable         102,000,000 102,000,000 131,000,000      
Related Party                    
Related Party Transaction [Line Items]                    
Accounts Payable, Current         $ 460,000,000 $ 460,000,000 400,000,000      
Investment funding commitments, percentage         50.00% 50.00%        
Manufacturing capacity percent operating         100.00% 100.00%        
Costs incurred associated with reduction in utilization           $ 11,000,000 75,000,000 249,000,000    
Net transfers from (to) Western Digital Corporation per Consolidated Statements of Shareholders’ Equity           0 (585,000,000) 275,000,000    
Tax indemnification liability         $ 112,000,000 112,000,000       $ 112,000,000
Notes payable         550,000,000 550,000,000        
Repayments of debt           6,000,000        
Related Party | WDC Subsidiaries                    
Related Party Transaction [Line Items]                    
Notes payable         553,000,000 553,000,000        
Related Party | Research And Development Commitments                    
Related Party Transaction [Line Items]                    
Related party transaction           138,000,000        
Related Party | Reimbursement of Short-Term Employee Incentives                    
Related Party Transaction [Line Items]                    
Related party transaction           22,000,000        
Related Party | Transition Services Agreement                    
Related Party Transaction [Line Items]                    
Related party expense           2,000,000 5,000,000      
Related Party | Flash Ventures                    
Related Party Transaction [Line Items]                    
Payments for equity method investments           3,600,000,000 3,400,000,000 3,400,000,000    
Proceeds from distributions           107,000,000        
Distributions from Flash Ventures             176,000,000 $ 0    
Accounts Payable, Current         $ 318,000,000 $ 318,000,000 279,000,000      
Extension Agreements | Related Party                    
Related Party Transaction [Line Items]                    
Other commitment                 $ 1,200,000,000  
Flash Ventures                    
Related Party Transaction [Line Items]                    
Ownership percentage         49.90% 49.90%        
Flash Ventures | Future Building Depreciation Payments | Related Party                    
Related Party Transaction [Line Items]                    
Other commitment         $ 402,000,000 $ 402,000,000        
Exchange rate         161.26 161.26        
To be paid year one         $ 118,000,000 $ 118,000,000        
To be paid year two         172,000,000 172,000,000        
To be paid year three         62,000,000 62,000,000        
To be paid year four         50,000,000 50,000,000        
To be paid year five         $ 50,000,000 $ 50,000,000        
Flash Ventures | Kioxia Corporation                    
Related Party Transaction [Line Items]                    
Ownership percentage         50.10% 50.10%        
K1, K2, And Y7 Facilities | Future Building Depreciation Payments | Related Party                    
Related Party Transaction [Line Items]                    
Other commitment         $ 840,000,000 $ 840,000,000 946,000,000      
K1, K2, And Y7 Facilities | Future Building Depreciation Payments | Related Party | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent                    
Related Party Transaction [Line Items]                    
Other commitment         133,000,000 133,000,000 131,000,000      
K1, K2, And Y7 Facilities | Future Building Depreciation Payments | Related Party | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent                    
Related Party Transaction [Line Items]                    
Other commitment         707,000,000 707,000,000 $ 815,000,000      
SanDisk Semiconductor (Shanghai) Co. Ltd.                    
Related Party Transaction [Line Items]                    
Ownership percentage       20.00%            
Equity investment       $ 158,000,000 $ 167,000,000 $ 167,000,000        
Unis Venture                    
Related Party Transaction [Line Items]                    
Ownership percentage         48.00% 48.00%        
Unis Venture | Revenue from Contract with Customer | Product Concentration Risk                    
Related Party Transaction [Line Items]                    
Concentration risk, percentage           1.00% 1.00% 1.00%    
Unis Venture | Unissoft (Wuxi) Group Co Ltd.                    
Related Party Transaction [Line Items]                    
Ownership percentage         52.00% 52.00%