Financial Instruments and Fair Value Measurements (Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis) (Details) - Recurring - USD ($) $ in Millions	Jun. 26, 2015	Sep. 26, 2014
Assets:
Debt and equity securities held in rabbi trusts	$ 35.9	$ 35.7
Foreign exchange forward and option contracts	3.6
Total assets at fair value	39.5	35.7
Liabilities:
Deferred compensation liabilities	20.1	15.0
Contingent consideration and acquired contingent liabilities	175.4	202.8
Foreign exchange forward and option contracts	0.9	0.2
Total liabilities at fair value	196.4	218.0
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Debt and equity securities held in rabbi trusts	24.5	22.9
Foreign exchange forward and option contracts	3.6
Total assets at fair value	28.1	22.9
Liabilities:
Deferred compensation liabilities	0.0	0.0
Contingent consideration and acquired contingent liabilities	0.0	0.0
Foreign exchange forward and option contracts	0.9	0.2
Total liabilities at fair value	0.9	0.2
Significant Other Observable Inputs (Level 2)
Assets:
Debt and equity securities held in rabbi trusts	11.4	12.8
Foreign exchange forward and option contracts	0.0
Total assets at fair value	11.4	12.8
Liabilities:
Deferred compensation liabilities	20.1	15.0
Contingent consideration and acquired contingent liabilities	0.0	0.0
Foreign exchange forward and option contracts	0.0	0.0
Total liabilities at fair value	20.1	15.0
Significant Unobservable Inputs (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	175.4	202.8
Foreign exchange forward and option contracts	0.0	0.0
Total liabilities at fair value	$ 175.4	$ 202.8