Selected Quarterly Financial Data (Unaudited) - Selected Quarterly Financial Data (Parenthetical) (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly Financial Information [Line Items]
Includes (loss) income from discontinued operations, net of tax	$ (678,000)	$ (464,000)	$ (244,000)	$ (194,000)	$ (4,779,000)	$ (261,000)	$ 593,000	$ (190,000)	$ (1,580,000)	$ (4,637,000)	$ (7,226,000)
Income from unrecognized tax position relate to discontinued operation							787,000
Income tax refund from discontinued operations							619,000
Income tax interest refund from discontinued operations							168,000
Charges net of tax related to environmental remediation costs at SurfTech					5,151,000
Pennsauken Site [Member] | Environmental Remediation Liability [Member]
Quarterly Financial Information [Line Items]
Charges net of tax related to environmental remediation costs at SurfTech					$ 5,151,000