Stockholders' Equity And Stock-Based Compensation Stockholders' Equity And Stock- Based Compensation - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Millions					3 Months Ended	12 Months Ended
	Jul. 20, 2015	Apr. 20, 2015	Jan. 19, 2015	Oct. 21, 2014	Sep. 25, 2015	Sep. 25, 2015	Sep. 26, 2014	Sep. 27, 2013
Statement of Stockholders' Equity [Abstract]
Cash dividend declared per common share	$ 0.1	$ 0.1	$ 0.1	$ 0.1	$ 0.12	$ 0.42	$ 0.00	$ 4.00
Dividends	$ 10.2	$ 10.3	$ 10.3	$ 10.2	$ 12.1