Restructuring and Impairment Charges (Restructuring and Impairment Charges) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended					9 Months Ended
	Sep. 30, 2013		Jun. 30, 2013	Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Total restructuring charges for cost of sales	$ 0			$ 318		$ 368		$ 1,454
Restructuring and Impairment
Severance and other employee related costs								1,600
Total charges for restructuring and impairment	1,231			1,766		5,756		9,949
High Performance Foams [Member]
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation expense	0			179		0		764
Inventory impairment	0			0		0		191
Union ratification bonus				0		181		0
Restructuring and Impairment
Fixed asset impairment for Bisco and Poron asset disposal	0			0		0		79
Printed Circuit Materials [Member]
Restructuring Cost and Reserve [Line Items]
Union ratification bonus				0		179		0
Power Electronics Solutions [Member] | Curamik Electronics Solutions [Member]
Restructuring Cost and Reserve [Line Items]
Union ratification bonus				0		5		0
Power Electronics Solutions [Member] | Power Distribution Systems [Member]
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation expense	0			139		0		499
Union ratification bonus				0		3		0
Restructuring and Impairment
Impairment of investment related receivable	0			0		0		264
Other [Member]
Restructuring Cost and Reserve [Line Items]
Inventory impairment	0			0		0		0
Pension Benefits [Member]
Restructuring and Impairment
Curtailment charge			1,537			1,537
Employee Severance [Member]
Restructuring and Impairment
Severance and other employee related costs	1,200		3,000
Employee Severance [Member] | High Performance Foams [Member]
Restructuring and Impairment
Severance and other employee related costs	94	[1]		0	[1]	1,345	[1]	3,088	[1]
Employee Severance [Member] | Printed Circuit Materials [Member]
Restructuring and Impairment
Severance and other employee related costs	93	[1]		0	[1]	802	[1]	3,046	[1]
Employee Severance [Member] | Power Electronics Solutions [Member] | Curamik Electronics Solutions [Member]
Restructuring and Impairment
Severance and other employee related costs	877	[1]		506		2,495	[1]	1,463
Employee Severance [Member] | Power Electronics Solutions [Member] | Power Distribution Systems [Member]
Restructuring and Impairment
Severance and other employee related costs	154	[1]		27	[1]	999	[1]	504	[1]
Employee Severance [Member] | Other [Member]
Restructuring and Impairment
Severance and other employee related costs	13	[1]		0	[1]	115	[1]	272	[1]
Facility Closing [Member] | High Performance Foams [Member]
Restructuring and Impairment
Severance and other employee related costs	$ 0			$ 1,233		$ 0		$ 1,233

[1] For the nine month period ended September 30, 2013, this includes a pension curtailment charge of $1.5 million. For the nine month period ended September 30, 2012, this includes a net charge of $1.6 million, related to the early retirement program implemented in the first quarter of 2012. See Note 8 - "Pension Benefits and Other Post Retirement Plans" for further information.