Derivative Financial Instruments Scheduel of Offsetting of Derivative Assets (Details) - USD ($) $ in Thousands	Jun. 28, 2015	Dec. 31, 2014
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	$ 509	$ 2,416
Gross Amounts Offset in the balance sheet	0	0
Net Amounts of Assets Presented in the Balance Sheet	509	2,416
Financial Instruments	(509)	(447)
Cash Collateral Pledged	0	0
Net Amounts	0	1,969
Barclays [Member]
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	97	319
Gross Amounts Offset in the balance sheet	0	0
Net Amounts of Assets Presented in the Balance Sheet	97	319
Financial Instruments	(97)	(16)
Cash Collateral Pledged	0	0
Net Amounts	0	303
Wells Fargo Bank [Member]
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	412	2,097
Gross Amounts Offset in the balance sheet	0	0
Net Amounts of Assets Presented in the Balance Sheet	412	2,097
Financial Instruments	(412)	(431)
Cash Collateral Pledged	0	0
Net Amounts	$ 0	$ 1,666