Name:	dei_DocumentFiscalYearFocus
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Balance Type:	na
Period Type:	duration

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

No definition available.

Name:	dei_DocumentPeriodEndDate
Namespace Prefix:	dei_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

The aggregate principal amount of debt instruments sold during the period.

No definition available.

Name:	stx_DebtInstrumentAggregatePrincipalAmountSold
Namespace Prefix:	stx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The "applicable premium" will be equal to the greater of (1) this percentage of the principal amount of the notes, or (2) the excess, if any, of (a) the present value of the redemption price on a certain specified date plus interest payments due through the specified date, discounted at the applicable Treasury rate as of the redemption date plus basis points at a specified amount over (b) the principal amount of such note.

No definition available.

Name:	stx_DebtInstrumentApplicablePremiumPercentageOfPrincipalAmount
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Data Type:	num:percentItemType
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Period Type:	instant

Represents the percentage of principal amount at which the entity may redeem the debt instrument.

No definition available.

Name:	stx_DebtInstrumentFutureRedemptionPriceAsPercentageOfOriginalPrincipal
Namespace Prefix:	stx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the maximum percentage of the aggregate principal amount of the debt instruments that the entity may redeem with net cash proceeds of certain equity offerings.

No definition available.

Name:	stx_DebtInstrumentRedemptionWithNetProceedsFromEquityOfferingsAsPercentageOfPrincipal
Namespace Prefix:	stx_
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Period Type:	instant

The maximum amount available for issuances of letters of credit under the revolving credit facility.

No definition available.

Name:	stx_LineOfCreditFacilityAvailableForIssuancesOfLettersOfCreditMaximum
Namespace Prefix:	stx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of letters of credit issued under the credit facility.

No definition available.

Name:	stx_LineOfCreditFacilityLettersOfCreditOutstanding
Namespace Prefix:	stx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

For long-term debt, the maximum number of days notice that the entity is required to give after the date the debt becomes redeemable.

No definition available.

Name:	stx_LongTermDebtRedeemableOptionNoticePeriodHighEndOfRange
Namespace Prefix:	stx_
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Period Type:	duration

For long-term debt, the minimum number of days notice that the entity is required to give after the date the debt becomes redeemable.

No definition available.

Name:	stx_LongTermDebtRedeemableOptionNoticePeriodLowEndOfRange
Namespace Prefix:	stx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Ratio of redemption price of long-term debt to be redeemed before applicable premiums and unpaid interest, if any.

No definition available.

Name:	stx_RedemptionPriceAsPercentageOfPrincipalAmount
Namespace Prefix:	stx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

This element represents the percentage spread over the applicable treasury rate. The sum of this spread and the applicable treasury rate is the discount rate in the present value calculation of the redemption price of the outstanding notes.

No definition available.

Name:	stx_SpreadOverTreasuryRateUsedInCalculationOfRedemptionPrice
Namespace Prefix:	stx_
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Balance Type:	na
Period Type:	instant

- Details

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

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Interest rate stated in the contractual debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Details

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Gross amount of debt extinguished.

No definition available.

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Balance Type:	debit
Period Type:	duration

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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.

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-Publisher FASB

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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-Paragraph 19, 22

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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-Glossary Financing Activities

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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-Publisher FASB

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