Name:	stx_BusinessAcquisitionsProFormaAdjustmentsForAdditionalDepreciationAndAmortization
Namespace Prefix:	stx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of comparative prior annual reporting period.

No definition available.

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

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of comparative prior annual reporting period.

No definition available.

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

- Details

Name:	us-gaap_BusinessAcquisitionProFormaInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_BusinessCombinationProFormaInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph r(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

Name:	us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.