Accumulated Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income by Component, Net of Tax (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Other expense, net	$ (2.5)us-gaap_OtherNonoperatingIncomeExpense	$ (1.7)us-gaap_OtherNonoperatingIncomeExpense
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	833.7us-gaap_StockholdersEquity
Other comprehensive (loss) income	(5.5)	0.3
Ending balance	831.1us-gaap_StockholdersEquity	825.2us-gaap_StockholdersEquity
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3.0)	18.1
Other comprehensive income (loss) before reclassifications	(8.4)
Amounts reclassified from accumulated other comprehensive income	(0.2)
Other comprehensive (loss) income	(8.6)	0.4
Ending balance	(11.6)	18.5
Unrealized Gains and Losses on Investment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	56.3	44.8
Other comprehensive income (loss) before reclassifications	3.1
Amounts reclassified from accumulated other comprehensive income	0
Other comprehensive (loss) income	3.1	(0.1)
Ending balance	59.4	44.7
Pension Liability Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2.2)	(1.5)
Other comprehensive income (loss) before reclassifications	0
Amounts reclassified from accumulated other comprehensive income	0
Other comprehensive (loss) income	0	0
Ending balance	(2.2)	(1.5)
Accumulated Other Comprehensive Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	51.1	61.4
Other comprehensive income (loss) before reclassifications	(5.3)
Amounts reclassified from accumulated other comprehensive income	(0.2)
Other comprehensive (loss) income	(5.5)	0.3
Ending balance	45.6	61.7
Reclassification out of Accumulated Other Comprehensive Income \| Foreign Currency Translation Adjustments
Other expense, net	$ (0.2)

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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-Publisher FASB

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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