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Related Parties and Related Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	May 31, 2019	Jan. 01, 2021	Jan. 03, 2020	Jan. 01, 2021	Jan. 03, 2020	Jul. 03, 2020
Guarantor Obligations [Line Items]
Accounts payable to related parties		$ 393		$ 393		$ 407
Investment funding commitments		50.00%		50.00%
Costs associated with underutilized capacity as a result of unexpected power outage incident					$ 68
Partial insurance recovery of business interruption				$ 75
Western Digital Corp \| Minimum
Guarantor Obligations [Line Items]
Investment funding commitments		49.90%		49.90%
Western Digital Corp \| Maximum
Guarantor Obligations [Line Items]
Investment funding commitments		50.00%		50.00%
Flash Ventures
Guarantor Obligations [Line Items]
Investments in Flash Ventures		$ 1,210	$ 648	$ 2,190	$ 1,330
Accounts payable to related parties		393		393		$ 407
Flash Ventures
Guarantor Obligations [Line Items]
Remaining committed prepayments		$ 149		$ 149
Unis Venture
Guarantor Obligations [Line Items]
Equity method investment, ownership percentage		49.00%		49.00%
Unissoft (Wuxi) Group Co Ltd. \| Unis Venture
Guarantor Obligations [Line Items]
Partner's ownership in venture business		51.00%		51.00%
Prepayments of Future Depreciation \| Flash Ventures
Guarantor Obligations [Line Items]
Other commitment	$ 360
Other commitment, period	3 years
Revenue from Contract with Customer \| Unis Venture \| Product Concentration Risk
Guarantor Obligations [Line Items]
Concentration risk, percentage		3.00%	1.00%	3.00%	1.00%
Accounts Receivable \| Product Concentration Risk \| Unis Venture
Guarantor Obligations [Line Items]
Concentration risk, percentage				7.00%		4.00%