Restructuring, Reorganization, Relocation and Severance (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Apr. 01, 2012	Mar. 31, 2013 Group Structure Reorganization [Member]	Mar. 31, 2013 Group Structure Reorganization [Member]	Dec. 31, 2012 Group Structure Reorganization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, reorganization, relocation and severance expense	$ 695,000	$ 0		$ 700,000	$ 2,900,000
Restructuring Reserve [Roll Forward]
Beginning accrued liability	2,692,000		2,692,000
Charged to expense, net	695,000		695,000
Expenditures	(511,000)		(511,000)
Write-offs and adjustments	(80,000)		(80,000)
Ending accrued liability	2,796,000		2,796,000
Expected additional cost of restructuring plan				600,000
Expected total cost of restructuring plan				$ 4,200,000