Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

Debt Instrument, Base Rate Applicable Margin

+ References

No definition available.

+ Details

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Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, EURIBOR Applicable Margin

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentEURIBORApplicableMargin
Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, EURIBOR Floor

+ References

No definition available.

+ Details

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Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, LIBOR Applicable Margin

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentLIBORApplicableMargin
Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, LIBOR Floor

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentLIBORFloor
Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Mandatory Repayment of Principal

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentMandatoryRepaymentofPrincipal
Namespace Prefix:	wdc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Prepayment Fee Percentage

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentPrepaymentFeePercentage
Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The required quarterly principal payment percentage on the Term Loan B Facilities principal amount beginning in September 2016.

+ References

No definition available.

+ Details

Name:	wdc_DebtInstrumentRequiredQuarterlyPrincipalPayment
Namespace Prefix:	wdc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percent Limitation on Pledges of Capital of Foreign Subsidiaries

+ References

No definition available.

+ Details

Name:	wdc_PercentLimitationonPledgesofCapitalofForeignSubsidiaries
Namespace Prefix:	wdc_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_NewCreditFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_SecuredNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_UnsecuredNotesMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_NotesMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_TermLoanAMember
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_EuroTermLoanBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=wdc_TermLoanBFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_BridgeLoanMember
Namespace Prefix:
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Balance Type:
Period Type:

Subsequent Events (Details)	Jan. 21, 2017	May. 31, 2016 USD ($)	May. 09, 2016 EUR (€)	May. 09, 2016 USD ($)	Apr. 30, 2016 USD ($)	Apr. 29, 2016 EUR (€)	Apr. 29, 2016 USD ($)	Apr. 13, 2016 USD ($)
Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Prepayment Fee Percentage						1.00%	1.00%
Subsequent Event
Subsequent Event [Line Items]
Debt Instrument, Face Amount					$ 18,100,000,000
New Credit Facilities \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Face Amount				$ 10,000,000,000
Secured Notes \| Subsequent Event \| Senior Notes
Subsequent Event [Line Items]
Debt Instrument, Face Amount								$ 1,875,000,000
Debt Instrument, Interest Rate, Stated Percentage								7.375%
Unsecured Notes \| Subsequent Event \| Senior Notes
Subsequent Event [Line Items]
Debt Instrument, Face Amount								$ 3,350,000,000
Debt Instrument, Interest Rate, Stated Percentage								10.50%
Notes \| Subsequent Event \| Senior Notes
Subsequent Event [Line Items]
Debt Instrument, Redemption Price, Percentage	100.00%
Term Loan A \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Face Amount							$ 4,125,000,000.000
U.S. Term Loan B \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Face Amount				$ 3,750,000,000.00			$ 3,750,000,000.00
Debt Instrument, Interest Rate, Stated Percentage						6.25%	6.25%
Debt Instrument, LIBOR Floor						0.75%	0.75%
Debt Instrument, LIBOR Applicable Margin						5.50%	5.50%
Debt Instrument, Base Rate Applicable Margin						4.50%	4.50%
Euro Term Loan B \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Face Amount \| €			€ 885,000,000			€ 885,000,000
Debt Instrument, Interest Rate, Stated Percentage						6.00%	6.00%
Debt Instrument, EURIBOR Floor						0.75%	0.75%
Debt Instrument, EURIBOR Applicable Margin						5.25%	5.25%
Revolving Credit Facility \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 1,000,000,000.0
Revolving Credit Facility \| Subsequent Event \| Letter of Credit \| Line of Credit
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 200,000,000
Term Loan B Facilities \| Subsequent Event \| Line of Credit
Subsequent Event [Line Items]
Debt Instrument, Required Quarterly Principal Payment			0.25%	0.25%
Percent Limitation on Pledges of Capital Stock of Foreign Subsidiaries						0.65	0.65
Debt Instrument, Mandatory Repayment of Principal (more than)							$ 100,000,000
Bridge Loan \| Subsequent Event
Subsequent Event [Line Items]
Debt Instrument, Face Amount		$ 3,000,000,000