Share-Based Compensation Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 29, 2019	Sep. 28, 2019
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted in period (in shares)		500,000
Aggregate grant date fair value		$ 68.0
Vesting period		3 years
Market Stock Units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted in period (in shares)		100,000
Aggregate grant date fair value		$ 7.0
Vesting period		3 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period (in shares)		200,000
Aggregate grant date fair value		$ 7.0
Vesting period		3 years
Performance Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period (in shares)		200,000
Aggregate grant date fair value		$ 7.0
Vesting period		3 years
Performance Stock Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate grant date fair value	$ 5.5
Performance period		3 years
VaaS \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted in period (in shares)		400,000
Aggregate grant date fair value		$ 38.0
Service period		1 year
WatchGuard \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted in period (in shares)		14,071
Aggregate grant date fair value		$ 2.3
Service period		2 years
WatchGuard \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted in period (in shares)		100,000
Aggregate grant date fair value		$ 13.8
Service period		2 years

Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Period

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Grant Date Fair Value

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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