Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Dec. 28, 2012	Jun. 27, 2014	Jun. 28, 2013	Jun. 29, 2012	Jul. 01, 2011
Income Tax Disclosure [Line Items]
Amount of tax benefit to be recognized		$ 37,000,000
Charge related to passage of California Proposition 39	88,000,000		88,000,000
Net undistributed earnings from foreign subsidiaries		8,200,000,000
Tax liability for undistributed earnings		2,700,000,000
Valuation allowances		128,000,000	133,000,000
Net Operating Loss benefits related to stock-based compensation deductions		11,000,000	13,000,000
Benefit Generated From Stock-Based Compensation		66,000,000
Excess tax benefits from employee stock plans		60,000,000	45,000,000	82,000,000
Expiration date of tax holidays in Malaysia, Philippines, Singapore and Thailand		2015 through 2025
Tax holidays and incentives increase net earnings		905,000,000	899,000,000	729,000,000
Tax holidays and incentives increase net earnings, shares		$ 3.74	$ 3.65	$ 2.98
Federal net operating loss carryforwards		440,000,000
State net operating loss carryforwards		480,000,000
Federal and state tax credit carryforwards		331,000,000
NOL carryforwards available to offset future federal taxable income expiration period		2020 to 2032
NOL Carryforwards available to offset future state taxable income expiration period		2017 to 2032
Credit carryforwards available to offset future taxable income		50,000,000
Credit carryforwards available to offset future taxable income expiration period		2016 to 2033
Reduction in ultimately realized amount of HGSTs NOL		39,000,000
Reduction in ultimately realized amount of credits		25,000,000
Amount of benefit that may be recognized for uncertain tax positions		largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement.
Unrecognized tax benefits		300,000,000	240,000,000	280,000,000	245,000,000
Western Digital Corporation [Member]
Income Tax Disclosure [Line Items]
Estimated impact of proposed IRS adjustments on pre-tax income		$ 970,000,000