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Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended
Jan. 02, 2015
Dec. 27, 2013
Jan. 02, 2015
Dec. 27, 2013
Income Tax Disclosure [Line Items]        
Income tax provision $ 20us-gaap_IncomeTaxExpenseBenefit $ 37us-gaap_IncomeTaxExpenseBenefit $ 57us-gaap_IncomeTaxExpenseBenefit $ 74us-gaap_IncomeTaxExpenseBenefit
Tax Benefit Resulting From Retroactive Extension Of Research And Development Credit 16wdc_TaxBenefitResultingFromRetroactiveExtensionOfResearchAndDevelopmentCredit   16wdc_TaxBenefitResultingFromRetroactiveExtensionOfResearchAndDevelopmentCredit  
Expiration date of tax holiday in Malaysia, Philippines, Singapore and Thailand     from 2015 through 2025  
Increase (Decrease) in liability for unrecognized tax benefits 9us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease   16us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease  
Unrecognized tax benefits 316us-gaap_UnrecognizedTaxBenefits   316us-gaap_UnrecognizedTaxBenefits  
Estimated impact of proposed IRS adjustments on Pre-tax income $ 200wdc_EstimatedImpactOfProposedIrsAdjustmentsOnPretaxIncome   $ 200wdc_EstimatedImpactOfProposedIrsAdjustmentsOnPretaxIncome