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Stockholders' Equity and Stock Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 28, 2020 | Jun. 30, 2019 | Jun. 28, 2020 | Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expense | $ 4.1 | $ 4.1 | $ 13.5 | $ 12.7
Performance-based restricted stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Percentage of shares that ultimately vest depending on growth in diluted earnings per share |  |  | 50.00% |
Percentage of shares that ultimately vest depending on the shareholder return relative to peer group of companies over vesting period |  |  | 50.00% |
Performance-based restricted stock | Non-employee directors and executive officers |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Granted (in shares) |  |  | 74,011 |
Granted, fair value (in dollars per share) |  |  | $ 99.85 |
Vesting period |  |  | 3 years |
Restricted stock units | Non-employee directors, executive officers and employees |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Granted (in shares) |  |  | 166,025 |
Granted, fair value (in dollars per share) |  |  | $ 83.90 |
Restricted stock units | Executive officers and employees |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period |  |  | 4 years |
Restricted stock units | Non-employee director |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period |  |  | 1 year |

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- Definition Represents the percentage of performance-based shares that ultimately vests, depending upon the fiscal year shareholder return relative to peer group of companies over the vesting period of the reporting entity. + References No definition available. + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the 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 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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