Derivative Instruments (Details) - USD ($) $ in Thousands	Jun. 28, 2015	Dec. 31, 2014
Derivative [Line Items]
Total outstanding derivative contracts	$ 294,726	$ 375,499
Cash Flow Hedging [Member]
Derivative [Line Items]
Total outstanding derivative contracts	142,000	222,000
Balance Sheet Hedges [Member]
Derivative [Line Items]
Total outstanding derivative contracts	$ 152,726	$ 153,499