Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2009
Income Taxes [Line Items]
Undistributed earnings of Canadian subsidiary	$ 4,700,000
Additional tax that might be payable upon repatriation of foreign earnings	326,000
Valuation allowance against net deferred tax assets	26,377,000	23,405,000	12,200,000
Unrecognized tax benefits that would impact effective tax rate	380,000
Unrecognized tax benefits, income tax penalties and interest expense	24,000
Benefit related interest expense	105,000
Unrecognized tax benefits, income tax penalties and interest accrued	90,000	171,000
Statutes Of limitations for tax returns	3 years
Minimum
Income Taxes [Line Items]
Operating loss carryforwards, expiration year	2013
Maximum
Income Taxes [Line Items]
Operating loss carryforwards subject to annual IRC section 382 limitation	5,300,000
Operating loss carryforwards, expiration year	2032
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Operating loss carryforwards, federal	39,300,000
State and Local Jurisdiction
Income Taxes [Line Items]
Operating loss carryforwards, federal	68,300,000
Operating loss carryforwards subject to annual IRC section 382 limitation	$ 8,600,000