Leases and Other Commitments - Additional Information (Details) - Sale Leaseback of California Manufacturing Facility $ in Millions	1 Months Ended
Apr. 30, 2019 USD ($) renewal_option
Sale Leaseback Transaction [Line Items]
Proceeds from sale leaseback transaction	$ 115
Loss on sale leaseback transaction	$ 25
Term of contract	15 years
Annual lease rate	$ 7
Annual percent increase	3.00%
Number of renewal options \| renewal_option	4
Renewal term	5 years
Maximum
Sale Leaseback Transaction [Line Items]
Renewal term	20 years

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

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- Definition

Lessee, Operating Lease, Lease Payment, Due Year One

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lessee, Operating Lease, Lease Payment, Percent Annual Increase

+ References

No definition available.

+ Details

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

- Definition

Lessee, Operating Lease, Number Of Renewal Options

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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