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.

No definition available.

+ Details

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

- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

+ Details

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

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=symc_FireglassLtd.andSkycureLtd.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions and Divestiture Acquisitions (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Jul. 31, 2017	Dec. 28, 2018	Dec. 29, 2017
Business Acquisition [Line Items]
Payments for acquisitions, net of cash acquired		$ 41	$ 402
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Payments for acquisitions, net of cash acquired		42	$ 66
Cash Acquired from Acquisition		$ 3
Fireglass, Ltd. and Skycure, Ltd.
Business Acquisition [Line Items]
Payments for acquisitions, net of cash acquired	$ 345
Cash Acquired from Acquisition	$ 15