Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Apr. 01, 2014	Mar. 31, 2015
Reconciliation unrecognized tax benefits
Income tax expense	$ 0.7	$ 1.3
Effective income tax rate (percent)	13.10%	30.20%
Deferred state income tax expense (benefit)		1.2
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount		0.1
Uncertain tax positions			$ 2.8