Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 29, 2018	Sep. 29, 2018
Statement of Financial Position [Abstract]
Accounts receivable, reserves	$ 13.0	$ 9.8
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	1,623,000	1,623,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	750,000,000	750,000,000
Common stock, issued (in shares)	289,045,000	287,853,000
Treasury stock (in shares)	17,537,000	12,560,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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