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Stockholders' Equity and Stock Compensation Plans - Summary (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2018 | Oct. 01, 2017 | Oct. 02, 2016
Stock-based compensation and related income tax benefits |  |  |
Total stock-based compensation | $ 19,582,000 | $ 13,450,000 | $ 12,964,000
Income tax benefit related to stock-based compensation | (5,288,000) | (4,715,000) | (4,656,000)
Stock-based compensation, net of tax benefit | $ 14,294,000 | 8,735,000 | 8,308,000
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) | 2,373,290 |  |
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 | $ 600,000 | $ 500,000 | $ 400,000
2005 EIP | Restricted Stock |  |  |
Stockholder's equity and stock compensation plans |  |  |
Vesting period | 3 years |  |
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) | 3,000,000 |  |
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% |  |

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