Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Loss Carryforwards [Line Items]
Excess tax benefits from employee restricted stock included in net operating loss carryforwards	$ 500,000
AMT credit carryforwards	500,000
Tax credit carryforwards, Expire year	2027
Unrecognized tax benefits	592,000	592,000	592,000
Valuation allowance	75,744,000	72,582,000
Increase in valuation allowance of deferred tax assets	3,200,000	12,100,000	7,200,000
Interest and penalties	3,000	3,000
Cumulative interest and penalties	44,000	41,000
Anticipated decrease in gross unrecognized tax benefits within next twelve months	200,000
Tax year under income tax examination	2011
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	101,200,000
Net operating loss carryforwards, expiry terms, federal taxes	Federal NOL carryforwards will expire from 2024 through 2034
Tax credit carryforwards	2,500,000
Federal income tax returns subject to examination description	Federal income tax returns of the Company are subject to IRS examination for the 2012 and 2013 tax years.
State [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	110,400,000
Net operating loss carryforwards, expiry terms, federal taxes	State NOL carryforwards will expire 2015 through 2034
Tax credit carryforwards	$ 700,000
Federal income tax returns subject to examination description	State income tax returns are subject to examination for a period of three to four years after filing.