Shareholders' Equity Shareholders' Equity - Investment by Unisplendour Corporation Limited (Details) - Unisplendour Corporation Limited [Member] - USD ($) $ / shares in Units, $ in Billions	3 Months Ended
Jul. 01, 2016	Oct. 02, 2015
Subsidiary, Sale of Stock [Line Items]
Minimal ownership percentage to maintain voting rights		10.00%
Scenario, Forecast [Member]
Subsidiary, Sale of Stock [Line Items]
Sale of stock, consideration received on transaction	$ 3.8
Sale of stock, number of shares issued in transaction	40,814,802
Sale of stock, price per share	$ 92.50
Sale of stock, terms, duration of position standstill	5 years
Sale of stock, terms, duration of shares lock-up	5 years

Cash received on stock transaction after deduction of issuance costs.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Sale Of Stock, Minimal Holding By Noncontrolling Interest To Hold Nomination Rights, Percent

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Sale of Stock, Terms, Duration of Position Standstill

+ References

No definition available.

+ Details

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Namespace Prefix:	wdc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Sale of Stock, Terms, Duration of Shares Lock-up

+ References

No definition available.

+ Details

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Namespace Prefix:	wdc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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