Represents the number every share or unit issued under the plan counts against aggregate share limit.

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- Definition

Represents the exercise price of the purchase right as a percentage of the fair market value of a share of common stock on the first day of the purchase right period.

+ References

No definition available.

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Represents the exercise price of the purchase right as a percentage of the fair market value of a share of common stock on the last day of the purchase right period.

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No definition available.

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- Definition

Represents the maximum amount that an employee is permitted to contribute during a purchase right period.

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

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No definition available.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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No definition available.

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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.

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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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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stockholders' Equity and Stock Compensation Plans - Summary (Details) - USD ($)	12 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Stock-based compensation and related income tax benefits
Total stock-based compensation	$ 19,424,000	$ 17,618,000	$ 19,582,000
Income tax benefit related to stock-based compensation	(4,318,000)	(4,016,000)	(5,288,000)
Stock-based compensation, net of tax benefit	$ 15,106,000	13,602,000	14,294,000
RSUs
Stockholder's equity and stock compensation plans
Vesting period	4 years
ESPP
Stockholder's equity and stock compensation plans
Available for future awards (in shares)	611,265
Maximum amount that an employee can contribute during a purchase right period	$ 5,000
Exercise price as percentage of fair market value on the first day of purchase right period	100.00%
Exercise price as percentage of fair market value on the last day of purchase right period	85.00%
Stock-based compensation and related income tax benefits
Total stock-based compensation	$ 1,200,000	$ 900,000	$ 600,000
2015 EIP
Stockholder's equity and stock compensation plans
The number every share or unit issued counts against aggregate share limit (in shares)	3
2018 EIP
Stockholder's equity and stock compensation plans
Available for future awards (in shares)	2,500,000
Grant date prior to March 6, 2006 \| 2005 EIP \| Stock options
Stockholder's equity and stock compensation plans
Vesting period	4 years
Expiration period	10 years
Grant date prior to March 6, 2006 \| 2005 EIP \| Stock options \| First anniversary of grant date and monthly thereafter
Stockholder's equity and stock compensation plans
Percentage of vesting rights after specified period	25.00%
Grant date on or after March 6, 2006 \| 2005 EIP \| Stock options
Stockholder's equity and stock compensation plans
Expiration period	8 years
Grant date on or after March 6, 2006 \| 2005 EIP \| Stock options \| Each anniversary of grant date
Stockholder's equity and stock compensation plans
Percentage of vesting rights after specified period	25.00%
Grant date on or after March 6, 2006 \| 2005 EIP \| RSUs \| Each anniversary of grant date
Stockholder's equity and stock compensation plans
Percentage of vesting rights after specified period	25.00%