Restructuring and Impairment Charges (Restructuring and Impairment Charges) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended																																					9 Months Ended		6 Months Ended	12 Months Ended			6 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Employee Severance [Member]	Dec. 31, 2012 High Performance Foams [Member]	Dec. 31, 2011 High Performance Foams [Member]	Dec. 31, 2010 High Performance Foams [Member]	Dec. 31, 2012 High Performance Foams [Member] Employee Severance [Member]	Dec. 31, 2011 High Performance Foams [Member] Employee Severance [Member]	Dec. 31, 2010 High Performance Foams [Member] Employee Severance [Member]	Dec. 31, 2012 High Performance Foams [Member] Facility Closing [Member]	Dec. 31, 2011 High Performance Foams [Member] Facility Closing [Member]	Dec. 31, 2010 High Performance Foams [Member] Facility Closing [Member]	Dec. 31, 2012 Composite Material Division [Member]	Dec. 31, 2011 Composite Material Division [Member]	Dec. 31, 2010 Composite Material Division [Member]	Dec. 31, 2012 Printed Circuit Materials [Member]	Dec. 31, 2011 Printed Circuit Materials [Member]	Dec. 31, 2010 Printed Circuit Materials [Member]	Dec. 31, 2012 Other [Member]	Dec. 31, 2011 Other [Member]	Dec. 31, 2010 Other [Member]	Dec. 31, 2012 Power Distribution Systems [Member] Power Electronics Solutions [Member]	Dec. 31, 2011 Power Distribution Systems [Member] Power Electronics Solutions [Member]	Dec. 31, 2010 Power Distribution Systems [Member] Power Electronics Solutions [Member]	Dec. 31, 2012 Curamik Electronics Solutions [Member] Power Electronics Solutions [Member]	Dec. 31, 2011 Curamik Electronics Solutions [Member] Power Electronics Solutions [Member]	Dec. 31, 2010 Curamik Electronics Solutions [Member] Power Electronics Solutions [Member]	Dec. 31, 2012 Power Distribution Systems [Member]	Dec. 31, 2011 Power Distribution Systems [Member]	Dec. 31, 2010 Power Distribution Systems [Member]	Dec. 31, 2012 Other [Member]	Dec. 31, 2011 Other [Member]	Dec. 31, 2010 Other [Member]	Dec. 31, 2012 Curamik Electronics Solutions [Member]	Dec. 31, 2011 Curamik Electronics Solutions [Member]	Dec. 31, 2010 Curamik Electronics Solutions [Member]	Sep. 30, 2012 Curamik Electronics Solutions [Member] Employee Severance [Member]	Sep. 30, 2012 Curamik Electronics Solutions [Member] Facility Closing [Member]	Jun. 30, 2012 High Performance Foams [Member]	Dec. 31, 2012 High Performance Foams [Member]	Dec. 31, 2011 High Performance Foams [Member]	Dec. 31, 2010 High Performance Foams [Member]	Jun. 30, 2012 High Performance Foams [Member] Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Accelerated Depreciation					$ 764	$ 0	$ 0																$ 499	$ 0	$ 0
Inventory Write-down		1,805	0		191	0	0							393	0	0
Restructuring, Settlement and Impairment Provisions	1,847	0	0
Impairment of Long-Lived Assets to be Disposed of					79	441	0
Restructuring and Related Cost, Expected Cost																													149	0	0	356	0	0	3,774	0	0	3,774	400	861	861	0	0	200
Restructuring Charges	15,929			1,600				2,188	0	0	1,442	0	0				2,915	0	0	255	0	0	423	0	0	1,376	0	0
Other than Temporary Impairment Losses, Investments																							264	0	0
Restructuring Costs and Asset Impairment Charges	$ 14,082	$ 441	$ 0