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Stockholders' Equity and Stock Compensation Plans - Narrative (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Oct. 03, 2021 | Sep. 27, 2020 | Sep. 29, 2019 | Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Options granted in the period (in shares) | 0 | 0 |  |
Stock options exercised | $ 11,250,000 | $ 10,334,000 | $ 11,751,000 |
Stock-based compensation expense | 23,067,000 | 19,424,000 | 17,618,000 |
Stock options |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Unrecognized stock-based compensation cost | $ 100,000 |  |  |
Weighted-average period to recognize the unrecognized compensation cost | 1 year |  |  |
Aggregate intrinsic value of options exercised | $ 29,400,000 | 22,400,000 | 20,400,000 |
Stock options exercised | 11,300,000 | 10,300,000 | 11,800,000 |
Income tax benefit realized from exercises of nonqualified stock options and disqualifying dispositions of qualified options | $ 12,900,000 | $ 8,300,000 | $ 6,400,000 |
RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 4 years |  |  |
Awards granted (in shares) | 117,934 | 167,525 | 179,478 |
Weighted-average grant date fair value (in dollars per share) | $ 122.02 | $ 83.92 | $ 66.26 |
Awards outstanding (in shares) | 380,631 | 444,000 | 470,000 | 488,000
RSUs | Director |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 1 year |  |  |
PSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 3 years |  |  |
Percentage of shares that ultimately vest depending on growth in diluted earnings per share | 50.00% |  |  |
Percentage of shares that ultimately vest based on relative total shareholder return over the vesting period | 50.00% |  |  |
Awards granted (in shares) | 57,542 | 74,011 | 89,816 |
Weighted-average grant date fair value (in dollars per share) | $ 153.03 | $ 99.85 | $ 80.41 |
Awards outstanding (in shares) | 318,000 | 355,000 | 384,000 | 323,000
RSUs and PSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Unrecognized stock-based compensation cost | $ 31,600,000 |  |  |
Stock-based compensation expense | $ 20,900,000 | $ 17,700,000 | $ 15,400,000 |
2015 EIP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
The number every share or unit issued counts against aggregate share limit (in shares) | 3 |  |  |
2018 EIP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Available for future awards (in shares) | 2,300,000 |  |  |
ESPP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Available for future awards (in shares) | 487,023 |  |  |
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% |  |  |
Unrecognized stock-based compensation cost | $ 500,000 | 300,000 |  |
Stock options exercised | 10,705,000 | 8,715,000 | 6,844,000 |
Stock-based compensation expense | 2,000,000 | $ 1,200,000 | $ 900,000 |
Accumulated amount by participants to purchase the entity's common stock | $ 10,800,000 |  |  |
Grant date prior to March 6, 2006 | 2005 EIP | Stock options |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
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 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Percentage of vesting rights after specified period | 25.00% |  |  |
Grant date on or after March 6, 2006 | 2005 EIP | Stock options |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expiration period | 8 years |  |  |
Grant date on or after March 6, 2006 | 2005 EIP | Stock options | Each anniversary of grant date |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
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 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Percentage of vesting rights after specified period | 25.00% |  |  |

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