Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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

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

+ References

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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Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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

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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Balance Type:	na
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- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of write-off of deferred financing costs and debt discounts related to prepetition debt obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=34712771&loc=d3e56145-112766

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=49172455&loc=d3e55730-112764

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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

- Definition

Debt Instrument, LIBOR 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, Prepayment Fee Percentage

+ References

No definition available.

+ Details

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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

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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

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

- Details

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- Details

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- Details

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- Details

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Debt Credit Agreement (Details) € in Millions, $ in Millions			3 Months Ended
	Sep. 22, 2016 USD ($)	Aug. 17, 2016 USD ($)	Sep. 30, 2016 USD ($)	Apr. 29, 2016 EUR (€)	Apr. 29, 2016 USD ($)
Term Loan B [Member]
Debt Instrument [Line Items]
Debtor Reorganization Items, Write-off of Deferred Financing Costs and Debt Discounts			$ 227
U.S. Term Loan B [Member]
Debt Instrument [Line Items]
Repayments of Debt		$ 750
U.S. Term Loan B-1 [Member]
Debt Instrument [Line Items]
Debt Instrument, Required Quarterly Principal Payment		0.25%
Debt Instrument, Basis Spread on Variable Rate		3.75%
Debt Instrument, Interest Rate, Effective Percentage			4.50%
Debt Issuance Cost		$ 5
Unamortized Debt Issuance Expense		$ 5
Debt Instrument, LIBOR Floor		0.75%
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		2.75%
Euro Term Loan B-1 [Member]
Debt Instrument [Line Items]
Debt Instrument, Required Quarterly Principal Payment	0.25%
Debt Instrument, Basis Spread on Variable Rate	3.25%
Debt Instrument, Interest Rate, Effective Percentage			4.00%
Debt Issuance Cost	$ 2
Unamortized Debt Issuance Expense	$ 2
Debt Instrument, LIBOR Floor	0.75%
Line of Credit [Member] \| Term Loan A [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount					$ 4,125
2018			$ 206
2019			309
2020			413
2021			$ 3,197
Line of Credit [Member] \| Term Loan B [Member]
Debt Instrument [Line Items]
Percent Limitation on Pledges of Capital of Foreign Subsidiaries			0.65
Line of Credit [Member] \| U.S. Term Loan B [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount					$ 3,750
Debt Instrument, Prepayment Fee Percentage			1.00%
Line of Credit [Member] \| U.S. Term Loan B-1 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 3,000
Line of Credit [Member] \| Euro Term Loan B [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €				€ 885
Line of Credit [Member] \| Euro Term Loan B-1 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 885
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Term Loan A [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage			2.53%