XML 84 R68.htm IDEA: XBRL DOCUMENT v3.6.0.2
Income Taxes - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Operating Loss Carryforwards [Line Items]        
Gross tax credits $ (888,000) $ (2,846,000)    
Federal net operating loss carryforward expiration year   2033    
State net operating loss carryforward expiration year   2016    
Period of cumulative change in ownership 3 years      
Annual limitation on use of pre-ownership change net operating losses and tax credit carryforwards $ 3,700,000      
Excess income tax benefit associated with stock-based compensation 0 $ 596,000 $ 0  
Unrecognized federal and state tax benefits 657,000 259,000 657,000 $ 2,409,000
Unrecognized tax benefits $ 0 0 0  
Interest and penalties associated with unrecognized tax benefits     522,000  
Minimum [Member]        
Operating Loss Carryforwards [Line Items]        
Cumulative change in ownership percentage 50.00%      
State and Local Jurisdiction [Member]        
Operating Loss Carryforwards [Line Items]        
State NOL carryforwards $ 400,000 9,600,000 5,900,000  
Alternative minimum tax (ATM) remaining federal tax NOL carryforwards 326,500,000      
Portion of state NOL carryforwards, not able to be utilized before expiration 312,300,000 34,500,000 8,100,000  
Valuation allowance for deferred assets associated with state NOL carryforwards 13,100,000 1,200,000    
Deferred tax assets, operating loss carryforwad, excess tax benefits 2,900,000      
Federal And State Tax        
Operating Loss Carryforwards [Line Items]        
Unrecognized federal and state tax benefits 0 $ 1,200,000 $ 1,100,000  
Internal Revenue Service (IRS) [Member]        
Operating Loss Carryforwards [Line Items]        
Gross tax credits $ 8,100,000      
Tax carryforward period 20 years      
Tax credit carryforward expiration year 2034      
Alternative minimum tax (ATM) remaining federal tax NOL carryforwards $ 390,100,000      
Deferred tax assets, operating loss carryforwad, excess tax benefits $ 3,000,000