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Restructuring Charges (Details) (USD $)	3 Months Ended			12 Months Ended
Restructuring Charges (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2,200,000us-gaap_RestructuringCharges	$ 1,100,000us-gaap_RestructuringCharges	$ 2,200,000us-gaap_RestructuringCharges	$ 39,000us-gaap_RestructuringCharges	$ 5,546,000us-gaap_RestructuringCharges	$ 7,301,000us-gaap_RestructuringCharges
Restructuring Reserve [Roll Forward]
Restructuring charges	2,200,000us-gaap_RestructuringCharges	1,100,000us-gaap_RestructuringCharges	2,200,000us-gaap_RestructuringCharges	39,000us-gaap_RestructuringCharges	5,546,000us-gaap_RestructuringCharges	7,301,000us-gaap_RestructuringCharges
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges					2,000,000
Restructuring Reserve [Roll Forward]
Restructuring charges					2,000,000
2012 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date				9,400,000
Company estimate of the aggregate restructuring cost				10,000,000
Restructuring charges					2,096,000	7,301,000
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			906,000	84,000	906,000	0
Restructuring charges					2,096,000	7,301,000
Payments for Restructuring				(84,000)	(2,265,000)	(6,395,000)
Non-cash settlements					(653,000)
Balance at December 31, 2012	84,000			0	84,000	906,000
2012 Plan \| Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges					1,960,000	0
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			0	0	0	0
Restructuring charges					1,960,000	0
Payments for Restructuring				0	(1,307,000)	0
Non-cash settlements					(653,000)
Balance at December 31, 2012	0			0	0	0
2012 Plan \| Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges					136,000	7,301,000
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			906,000	84,000	906,000	0
Restructuring charges					136,000	7,301,000
Payments for Restructuring				(84,000)	(958,000)	(6,395,000)
Non-cash settlements					0
Balance at December 31, 2012	84,000			0	84,000	906,000
2012 Plan \| ESD Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges						3,400,000
Restructuring Reserve [Roll Forward]
Restructuring charges						3,400,000
2012 Plan \| MID
Restructuring Cost and Reserve [Line Items]
Restructuring charges						700,000
Restructuring Reserve [Roll Forward]
Restructuring charges						700,000
2012 Plan \| Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges						100,000
Restructuring Reserve [Roll Forward]
Restructuring charges						100,000
2012 Plan \| Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring charges						3,100,000
Restructuring Reserve [Roll Forward]
Restructuring charges						3,100,000
2013 Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges				39,000	3,450,000
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			0	1,865,000	0
Restructuring charges				39,000	3,450,000
Payments for Restructuring				(1,904,000)	(1,585,000)
Balance at December 31, 2012	1,865,000			0	1,865,000
2013 Plan \| Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges				0	195,000
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			0	133,000	0
Restructuring charges				0	195,000
Payments for Restructuring				(133,000)	(62,000)
Balance at December 31, 2012	133,000			0	133,000
2013 Plan \| Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges				39,000	3,255,000
Restructuring Reserve [Roll Forward]
Balance at December 31, 2011			0	1,732,000	0
Restructuring charges				39,000	3,255,000
Payments for Restructuring				(1,771,000)	(1,523,000)
Balance at December 31, 2012	1,732,000			0	1,732,000
2013 Plan \| ESD Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges					2,400,000
Restructuring Reserve [Roll Forward]
Restructuring charges					2,400,000
2013 Plan \| MID
Restructuring Cost and Reserve [Line Items]
Restructuring charges					100,000
Restructuring Reserve [Roll Forward]
Restructuring charges					100,000
2013 Plan \| Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges					900,000
Restructuring Reserve [Roll Forward]
Restructuring charges					900,000
2013 Plan \| Minimum
Restructuring Cost and Reserve [Line Items]
Company estimate of the aggregate restructuring cost				3,000,000
2013 Plan \| Maximum
Restructuring Cost and Reserve [Line Items]
Company estimate of the aggregate restructuring cost				$ 4,000,000