Accumulated Other Comprehensive Income (Schedule of Reclassifications out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions		12 Months Ended
		Sep. 25, 2015	Sep. 26, 2014
Equity [Abstract]
Amortization of unrealized loss on derivatives		$ 0.6	$ 0.6
Income tax provision		(0.2)	(0.1)
Net of income taxes		0.4	0.5
Amortization of pension and post-retirement benefit plans:
Net actuarial loss	[1]	9.4	8.1
Prior service credit	[1]	(4.6)	(9.9)
Plan settlements	[1]	6.0	3.8
Total before tax		10.8	2.0
Income tax provision		(4.1)	(0.6)
Net of income taxes		6.7	1.4
Total reclassifications for the period		$ 7.1	$ 1.9

[1] These accumulated other comprehensive income components are included in the computation of net periodic benefit cost. See Note 13 for additional details.