Stockholders' Equity, Equity Incentive Plans (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 30, 2017
Stockholders' Equity [Abstract]
Stock-based compensation expense	$ 27	$ 23	$ 20
Intrinsic value of options exercised	$ 43
2015 Plan [Member]
Stockholders' Equity [Abstract]
Shares authorized for grant (in shares)		12.5
Increase in shares authorized for grant (in shares)		5.0