Stock-Based Compensation - Fair Value of Stock Compensation (Details) - $ / shares	3 Months Ended	9 Months Ended
Jul. 04, 2020	Jun. 29, 2019	Jul. 04, 2020	Jun. 29, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Common shares that restricted stock units with each unit representing			1
Requisite service period			3 years
Employee stock
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected life in years	6 months	6 months	6 months	6 months
Volatility	63.70%	47.90%	53.00%	47.90%
Risk-free interest rate	0.54%	2.46%	1.27%	2.43%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Weighted average fair value per share	$ 43.35	$ 40.42	$ 43.81	$ 40.57
Performance restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Volatility			50.40%	43.70%
Risk-free interest rate			0.90%	2.90%
Weighted average fair value per share			$ 162.14	$ 117.43

common shares that restricted stock units with each unit representing

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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- Definition

The estimated measure of the 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.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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