Accrued Liabilities - Other - Accrued Liabilities - Other (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]
Taxes (other than income) and insurance	$ 667,000	$ 602,000
Commissions	634,000	680,000
Litigation and legal fees	118,000	138,000
Other professional fees	472,000	418,000
Environmental	4,820,000	5,334,000
Warranty	1,422,000	1,102,000
Deferred revenue	83,000	56,000
Acquisition earn-out, current	105,000	164,000
Other	3,065,000	2,092,000
Accrued liabilities - other	$ 11,386,000	$ 10,586,000