Shareholders' Equity (Capped Calls) (Details) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 28, 2019 shares	Sep. 30, 2017 shares	Sep. 28, 2019 shares $ / shares	Sep. 29, 2018 shares	Sep. 30, 2017 shares	Oct. 01, 2016 USD ($) shares $ / shares
Class of Stock [Line Items]
Additional paid in capital, capped calls | $						$ 7,935
Initial capped calls equivalent shares (in shares)						2,282,000
Capped calls settled, percentage		10.00%
Settlement of capped calls (in shares)		12,000		0
Original Capped Call Agreements | Minimum
Class of Stock [Line Items]
Strike price, capped calls (in dollars per share) | $ / shares						$ 50.40
Original Capped Call Agreements | Maximum
Class of Stock [Line Items]
Strike price, capped calls (in dollars per share) | $ / shares						$ 58.80
Amended Capped Call Agreements
Class of Stock [Line Items]
Capped calls outstanding equivalent shares (in shares)			2,054,000
Amended Capped Call Agreements | Minimum
Class of Stock [Line Items]
Strike price, capped calls (in dollars per share) | $ / shares			$ 50.40
Amended Capped Call Agreements | Maximum
Class of Stock [Line Items]
Strike price, capped calls (in dollars per share) | $ / shares			$ 57.97
Common Stock
Class of Stock [Line Items]
Settlement of capped calls (in shares)			(223,000)		(12,000)
Common Stock | Amended Capped Call Agreements
Class of Stock [Line Items]
Common stock to be received and retired under capped calls (in shares)	223,000