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Stockholders' Equity and Stock Compensation Plans - Stock Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 01, 2017 | Sep. 29, 2019 | Sep. 30, 2018 | Oct. 01, 2017
Number of Options (in thousands) |  |  |  |
Outstanding at the beginning of the year (in shares) |  | 1,355 |  |
Exercised (in shares) |  | (456) |  |
Forfeited (in shares) |  | (5) |  |
Outstanding at the end of the period (in shares) |  | 894 | 1,355 |
Vested or expected to vest at the end of the period (in shares) |  | 894 |  |
Exercisable at the end of the period (in shares) |  | 671 |  |
Weighted- Average Exercise Price per Share |  |  |  |
Outstanding at the beginning of the year (in dollars per share) |  | $ 30.87 |  |
Exercised (in dollars per share) |  | 26.21 |  |
Forfeited (in dollars per share) |  | 23.48 |  |
Outstanding at the end of the period (in dollars per share) |  | 33.28 | $ 30.87 |
Vested or expected to vest at the end of the period (in dollars per share) |  | 33.28 |  |
Exercisable at the end of the period (in dollars per share) |  | $ 30.75 |  |
Weighted- Average Remaining Contractual Term (in years) |  |  |  |
Outstanding at the end of the period |  | 5 years 29 days |  |
Vested or expected to vest at the end of the period |  | 5 years 29 days |  |
Exercisable at the end of the period |  | 4 years 3 months 29 days |  |
Aggregate Intrinsic Value (in thousands) |  |  |  |
Outstanding at the end of the period |  | $ 46,176 |  |
Vested or expected to vest at the end of the period |  | 46,176 |  |
Exercisable at the end of the period |  | $ 36,346 |  |
Assumptions used in the Black-Scholes option-pricing model |  |  |  |
Options granted in the period (in shares) |  | 0 |  |
Stock options exercised |  | $ 11,751 | $ 13,520 | $ 18,555
Stock options |  |  |  |
Assumptions used in the Black-Scholes option-pricing model |  |  |  |
Dividend yield | 1.00% |  | 1.00% |
Expected stock price volatility, minimum (as a percent) |  |  | 36.10% | 36.10%
Expected stock price volatility, maximum (as a percent) |  |  | 38.80% | 38.80%
Risk-free rate of return, annual, minimum (as a percent) |  |  | 1.70% | 1.70%
Risk-free rate of return, annual, maximum (as a percent) |  |  | 2.90% | 1.90%
Unrecognized compensation cost |  | $ 2,000 |  |
Weighted-average period to recognize the unrecognized compensation cost |  | 1 year |  |
Weighted-average fair value of stock options granted (in dollars per share) |  |  | $ 14.82 | $ 12.35
Aggregate intrinsic value of options exercised |  | $ 20,400 | $ 14,400 | $ 16,400
Stock options exercised |  | 11,800 | 13,500 | 18,600
Income tax benefit realized from exercises of nonqualified stock options and disqualifying dispositions of qualified options |  | $ 6,400 | $ 5,100 | $ 4,900

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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + 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 (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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