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Stockholders' Equity and Stock Compensation Plans - Stock Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2018 | Oct. 01, 2017 | Oct. 02, 2016
Number of Options (in thousands) |  |  |
Outstanding at the beginning of the year (in shares) | 1,753 |  |
Granted (in shares) | 171 |  |
Exercised (in shares) | (549) |  |
Forfeited (in shares) | (20) |  |
Outstanding at the end of the period (in shares) | 1,355 | 1,753 |
Vested or expected to vest at the end of the period (in shares) | 1,330 |  |
Exercisable at the end of the period (in shares) | 929 |  |
Weighted- Average Exercise Price per Share |  |  |
Outstanding at the beginning of the year (in dollars per share) | $ 27.18 |  |
Granted (in dollars per share) | 48.01 |  |
Exercised (in dollars per share) | 50.85 |  |
Forfeited (in dollars per share) | 26.90 |  |
Outstanding at the end of the period (in dollars per share) | 30.87 | $ 27.18 |
Vested or expected to vest at the end of the period (in dollars per share) | 30.94 |  |
Exercisable at the end of the period (in dollars per share) | $ 27.21 |  |
Weighted- Average Remaining Contractual Term (in years) |  |  |
Outstanding at the end of the period | 5 years 2 months 1 day |  |
Vested or expected to vest at the end of the period | 5 years 1 month 16 days |  |
Exercisable at the end of the period | 3 years 11 months 4 days |  |
Aggregate Intrinsic Value (in thousands) |  |  |
Outstanding at the end of the period | $ 50,689 |  |
Vested or expected to vest at the end of the period | 49,694 |  |
Exercisable at the end of the period | $ 38,152 |  |
Stock options |  |  |
Assumptions used in the Black-Scholes option-pricing model |  |  |
Dividend yield | 1.00% | 1.00% | 1.20%
Expected stock price volatility, minimum (as a percent) | 36.10% | 36.10% | 36.10%
Expected stock price volatility, maximum (as a percent) | 38.80% | 38.80% | 38.80%
Risk-free rate of return, annual, minimum (as a percent) | 1.70% | 1.70% | 1.60%
Risk-free rate of return, annual, maximum (as a percent) | 2.90% | 1.90% | 1.80%
Unrecognized compensation cost | $ 3,800 |  |
Weighted-average period to recognize the unrecognized compensation cost | 2 years |  |
Weighted-average fair value of stock options granted (in dollars per share) | $ 14.82 | $ 12.35 | $ 8.05
Aggregate intrinsic value of options exercised | $ 14,400 | $ 16,400 | $ 7,300
Net cash proceeds from the exercise of stock options | 13,500 | 18,600 | 18,000
Income tax benefit realized from exercises of nonqualified stock options and disqualifying dispositions of qualified options | $ 5,100 | $ 4,900 | $ 5,300

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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=109197908&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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