Fair Value Measurements (Reconciliation of Beginning and Ending Level 3 Net Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014	Jun. 30, 2013
Fair Value Disclosures [Abstract]
Balance beginning of period	$ (4,981)	$ (2,727)	$ (4,926)	$ (3,017)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	0	(1,100)	0	(1,100)
Payments	(72)	0	72	(64)
Change in fair value (included within selling, general and administrative expenses)	1,623	112	1,568	338
Balance end of period	$ (3,430)	$ (3,715)	$ (3,430)	$ (3,715)