Financial Instruments and Fair Value Measurements (Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis) (Details) - Recurring - USD ($) $ in Millions	Mar. 25, 2016	Sep. 25, 2015
Assets:
Debt and equity securities held in rabbi trusts	$ 34.2	$ 34.6
Foreign exchange forward and option contracts	1.9
Total assets at fair value	36.1	34.6
Liabilities:
Deferred compensation liabilities	22.1	20.0
Contingent consideration and acquired contingent liabilities	204.2	174.6
Foreign exchange forward and option contracts		3.3
Total liabilities at fair value	226.3	197.9
Level 1
Assets:
Debt and equity securities held in rabbi trusts	24.4	24.2
Foreign exchange forward and option contracts	1.9
Total assets at fair value	26.3	24.2
Liabilities:
Deferred compensation liabilities	0.0	0.0
Contingent consideration and acquired contingent liabilities	0.0	0.0
Foreign exchange forward and option contracts		3.3
Total liabilities at fair value	0.0	3.3
Level 2
Assets:
Debt and equity securities held in rabbi trusts	9.8	10.4
Foreign exchange forward and option contracts	0.0
Total assets at fair value	9.8	10.4
Liabilities:
Deferred compensation liabilities	22.1	20.0
Contingent consideration and acquired contingent liabilities	0.0	0.0
Foreign exchange forward and option contracts		0.0
Total liabilities at fair value	22.1	20.0
Level 3
Assets:
Debt and equity securities held in rabbi trusts	0.0	0.0
Foreign exchange forward and option contracts	0.0
Total assets at fair value	0.0	0.0
Liabilities:
Deferred compensation liabilities	0.0	0.0
Contingent consideration and acquired contingent liabilities	204.2	174.6
Foreign exchange forward and option contracts		0.0
Total liabilities at fair value	$ 204.2	$ 174.6