Fair Value Measurements (Assets and Liabilities at Fair Value on Recurring Basis) (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Millions, unless otherwise specified	Mar. 23, 2013		Dec. 29, 2012
Total [Member]
Assets:
Cash equivalents	$ 26.4		$ 96.5
Total	121.7		174.6
Liabilities:
Total	21.9		21.8
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Cash equivalents	0		91.0
Total	29.6		105.5
Liabilities:
Total	0		0
Significant Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents	26.4		5.5
Total	92.1		69.1
Liabilities:
Total	0		0
Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents	0		0
Total	0		0
Liabilities:
Contingent consideration	21.9		21.8
Total	21.9		21.8
Prepaid Expenses and Other Current Assets [Member] | Total [Member]
Assets:
Investments	62.3	[1]	44.2	[1]
Prepaid Expenses and Other Current Assets [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Investments	29.6	[1]	14.5	[1]
Prepaid Expenses and Other Current Assets [Member] | Significant Observable Inputs (Level 2) [Member]
Assets:
Investments	32.7	[1]	29.7	[1]
Prepaid Expenses and Other Current Assets [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Investments	0	[1]	0	[1]
Other Assets [Member] | Total [Member]
Assets:
Investments	33.0	[2]	33.9	[2]
Other Assets [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Investments	0	[2]	0	[2]
Other Assets [Member] | Significant Observable Inputs (Level 2) [Member]
Assets:
Investments	33.0	[2]	33.9	[2]
Other Assets [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Investments	0	[2]	0	[2]
Other Accrued Liabilities [Member] | Total [Member]
Liabilities:
Contingent consideration	21.9	[3]	21.8	[3]
Other Accrued Liabilities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Liabilities:
Contingent consideration	0	[3]	0	[3]
Other Accrued Liabilities [Member] | Significant Observable Inputs (Level 2) [Member]
Liabilities:
Contingent consideration	0	[3]	0	[3]
Other Accrued Liabilities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Liabilities:
Contingent consideration	$ 21.9	[3]	$ 21.8	[3]

[1] Included in Prepaid Expenses and Other Current Assets on the balance sheet.

[2] Included in Other Assets on the balance sheet.

[3] Included in Other Accrued Liabilities and Accrued Claims and Other Liabilities on the balance sheet.