Derivative Financial Instruments Derivatives Designated as Cash Flow Hedges (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2013	Jun. 29, 2012	Jun. 28, 2013	Jun. 29, 2012	Dec. 31, 2012
Derivative [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value	$ 71		$ 71		$ 0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	250	0	71	0
Interest Rate Swap [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	250		71	0
Minimum [Member]
Derivative [Line Items]
Derivative Liability, Notional Amount	70,000		70,000
Maximum [Member]
Derivative [Line Items]
Derivative Liability, Notional Amount	$ 90,000		$ 90,000