Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2015	Jun. 29, 2014	Jun. 28, 2015	Jun. 29, 2014
Defined Benefit Plan Disclosure [Line Items]
Benefits paid			$ 800
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year			2,300
Service cost	$ 11	$ 304	22	$ 325
Interest cost	307	293	615	586
Net amortization	134	29	267	59
Net periodic pension cost	$ 452	$ 626	$ 904	$ 970