Leases (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 30, 2014	Dec. 31, 2013	Jan. 01, 2013
Operating Leased Assets [Line Items]
Operating leases, lease term	10 years
Operating leases, rent expense	$ 35.7	$ 29.5	$ 24.6
Minimum [Member]
Operating Leased Assets [Line Items]
Operating leases, extension term	5 years
Maximum [Member]
Operating Leased Assets [Line Items]
Operating leases, extension term	15 years