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Restructuring, Reorganization, Relocation and Severance (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 29, 2015	Mar. 30, 2014	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance	$ (121)us-gaap_RestructuringCharges	$ 1,331us-gaap_RestructuringCharges
Restructuring Reserve [Roll Forward]
Beginning accrued liability	9,161us-gaap_RestructuringReserve	50us-gaap_RestructuringReserve
Restructuring, reorganization, relocation and severance	(121)us-gaap_RestructuringCharges	1,331us-gaap_RestructuringCharges
Expenditures	(4,834)us-gaap_PaymentsForRestructuring	(484)us-gaap_PaymentsForRestructuring
Write-offs and adjustments	(622)
Ending accrued liability	3,584us-gaap_RestructuringReserve	897us-gaap_RestructuringReserve
Second Quarter 2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance	(121)
Restructuring Reserve [Roll Forward]
Beginning accrued liability	9,161
Restructuring, reorganization, relocation and severance	(121)
Expenditures	(4,834)
Write-offs and adjustments	(622)
Ending accrued liability	3,584
Group Structure Reorganization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance		0
Restructuring Reserve [Roll Forward]
Beginning accrued liability		50
Restructuring, reorganization, relocation and severance		0
Expenditures		0
Ending accrued liability		50
First Quarter 2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance		1,331
Restructuring Reserve [Roll Forward]
Beginning accrued liability		0
Restructuring, reorganization, relocation and severance		1,331
Expenditures		(484)
Ending accrued liability		847
First Quarter 2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance		1,300
Restructuring Reserve [Roll Forward]
Restructuring, reorganization, relocation and severance		1,300
Group Structure Reorganization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance			1,100	2,900	4,000
Restructuring Reserve [Roll Forward]
Restructuring, reorganization, relocation and severance			$ 1,100	$ 2,900	$ 4,000