Shareholders' Equity - Shares of Common Stock (Details) - shares shares in Thousands	12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Increase (Decrease) in Shares of Common Stock Outstanding [Roll Forward]
Common stock outstanding, beginning balances (in shares)	17,772,945
Common stock repurchased (in shares)	(917,000)
Common stock outstanding, ending balances (in shares)	16,976,763	17,772,945
Common stock
Increase (Decrease) in Shares of Common Stock Outstanding [Roll Forward]
Common stock outstanding, beginning balances (in shares)	17,772,945	19,019,943	20,504,805
Common stock repurchased (in shares)	(917,270)	(1,380,819)	(1,622,198)
Common stock issued, net of shares withheld for employee taxes (in shares)	121,088	133,821	137,336
Common stock outstanding, ending balances (in shares)	16,976,763	17,772,945	19,019,943