Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Sep. 24, 2016	Sep. 26, 2015
Statement of Financial Position [Abstract]
Accounts receivable, reserves	$ 12.7	$ 11.1
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	1,623	1,623
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	750,000
Common stock, issued (in shares)	285,015	282,495
Treasury Stock, Shares	7,289