Employee Stock Plans - Activity Under Employee Stock Plans (Detail) shares in Millions	12 Months Ended
	Sep. 27, 2019 $ / shares shares
Number of Shares
Beginning balance (in shares) | shares	2.3
Granted (in shares) | shares	0.6
Canceled, expired or forfeited (in shares) | shares	(0.1)
Exercised (in shares) | shares	(0.6)
Ending balance (in shares) | shares	2.2
Weighted Average Exercise Price
Beginning balance (in dollars per share) | $ / shares	$ 85.82
Granted (in dollars per share) | $ / shares	123.33
Canceled, expired or forfeited (in dollars per share) | $ / shares	107.50
Exercised (in dollars per share) | $ / shares	77.11
Ending balance (in dollars per share) | $ / shares	$ 97.66