Common Stock Capital Shares Reserved For Future Issuance Annual Automatic Increase Percentage

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- Definition

The maximum number of common shares may be issued by an entity's.

+ References

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- Definition

Minimum increase common stock capital shares reserved for future issuance.

+ References

No definition available.

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- Definition

Percentage of payroll deduction on eligible common stock.

+ References

No definition available.

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- Definition

Share based compensation by share based payment arrangement instruments other than options expected to vest outstanding.

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award right of repurchase.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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 (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ 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
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-URI http://asc.fasb.org/extlink&oid=120381028&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.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ 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
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Stock option plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Sep. 26, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Rights Percentage		25.00%
Unrecognized compensation cost, stock options		$ 42.4
Unrecognized stock-based compensation expense, period for recognition		2 years 6 months
Options Grant date fair value		$ 20.76	$ 15.06	$ 7.08
Shares subject to right of repurchase		16,815
2018 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum annual increase in share reserved for issuance	999,900
Annual automatic Increase in share reserved for issuance	4.00%
2018 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares may be issued	5,856,505
2018 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum annual increase in share reserved for issuance	249,470
Annual automatic Increase in share reserved for issuance	1.00%
Aggregate number of common stock shares reserved for issuance	275,225	179,000	56,000
2018 ESPP [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payroll deduction to purchase common stock	15.00%
2015 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP eligible employee common stock purchase price ratio	85.00%
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement equity instruments other than options non vested outstanding grant date fair value		$ 32.96	$ 26.16
Restricted Stock Units (RSUs) [Member] \| 2018 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, stock options		$ 17.6
Unrecognized stock-based compensation expense, period for recognition		2 years 9 months 18 days
Phantom Share Units (PSUs) [Member] \| Revised Annual Equity Award Programme [Member] \| Executive Officers and Senior Level Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement instruments other than options expected to vest outstanding		225,396
Share based compensation by share based payment arrangement equity instruments other than options non vested outstanding grant date fair value		$ 43.06
Share based compensation by share based payment arrangement equity instruments other than options unrecognized compensation		$ 9.3
Unrecognized stock-based compensation expense, period for recognition		2 years
Phantom Share Units (PSUs) [Member] \| Revised Annual Equity Award Programme [Member] \| Minimum [Member] \| Executive Officers and Senior Level Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Rights Percentage		0.00%
Phantom Share Units (PSUs) [Member] \| Revised Annual Equity Award Programme [Member] \| Maximum [Member] \| Executive Officers and Senior Level Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Rights Percentage		150.00%