Supplemental Financial Statement Data - Inventories; Property, Plant and Equipment; and Other Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	Apr. 03, 2015	Jun. 27, 2014
Inventories:
Raw materials and component parts	$ 173	$ 168
Work-in-process	498	493
Finished goods	651	565
Total inventories	1,322us-gaap_InventoryNet	1,226us-gaap_InventoryNet
Property, plant and equipment:
Property, plant and equipment	8,520us-gaap_PropertyPlantAndEquipmentGross	8,123us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation	(5,469)	(4,830)
Property, plant and equipment, net	3,051us-gaap_PropertyPlantAndEquipmentNet	3,293us-gaap_PropertyPlantAndEquipmentNet
Other intangible assets:
Other intangible assets, gross	1,067wdc_OtherIntangibleAssetsGross	984wdc_OtherIntangibleAssetsGross
Accumulated amortization	(667)	(530)
Other intangible assets, net	$ 400us-gaap_OtherIntangibleAssetsNet	$ 454us-gaap_OtherIntangibleAssetsNet

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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