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Related Parties and Related Commitments and Contingencies - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	May 31, 2019 USD ($)	Apr. 02, 2021 USD ($) entity	Apr. 03, 2020 USD ($)	Apr. 02, 2021 USD ($) entity	Apr. 03, 2020 USD ($)	Jul. 03, 2020 USD ($)
Guarantor Obligations [Line Items]
Number of legal entities \| entity		3		3
Accounts payable to related parties		$ 397		$ 397		$ 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		$ 1,140	$ 842	$ 3,330	$ 2,360
Accounts payable to related parties		397		397		$ 407
Flash Ventures
Guarantor Obligations [Line Items]
Remaining committed prepayments		$ 108		$ 108
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				6.00%		4.00%