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Income Taxes - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Income Taxes [Line Items]      
Decrease in effective tax rate 89.30%    
Effective tax rate 12.50% 101.80% 35.80%
Increase (decrease) in effective tax rate due to tax reform (1.30%) 66.70%  
Decrease in effective tax rate due to change in U.S.federal corporate tax rate 14.00%    
Decrease in effective tax rate of goodwill impairment 6.90%    
Decrease in effective tax rate of valuation allownaces 3.70%    
Increase in effective tax rate due to remeasurement of deferred tax assets and liabilities for state tax 2.30%    
U.S. federal corporate tax rate 21.00% 35.00% 35.00%
Tax expense as adjustment to provisional amounts   $ 4,600,000  
Additional taxes for one-time transition tax   0  
Income inclusion amount in final transition tax computation   13,700,000  
Additional tax expense to adjust provisional estimate on remeasurement of U.S. deferred tax assets and liabilities   $ 1,700,000  
Valuation allowances against net deferred tax assets $ 13,232,000    
Gross federal net operating losses 1,300,000,000    
Gross canadian net operating losses 24,700,000    
Post-apportionment state net operating losses 735,000,000    
Unrecognized tax benefits $ 0    
Tax reform      
Income Taxes [Line Items]      
U.S. federal corporate tax rate 21.00% 35.00%  
Provisional income tax benefit   $ 219,000,000  
Operations Outside of North America      
Income Taxes [Line Items]      
Valuation allowances against net deferred tax assets $ 200,000    
State Jurisdictions      
Income Taxes [Line Items]      
Valuation allowances against net deferred tax assets $ 4,900,000    
Net operating loss carryforwards expiration, beginning year 2023    
Net operating loss carryforwards expiration, ending year 2038    
Canada      
Income Taxes [Line Items]      
Valuation allowances against net deferred tax assets $ 8,100,000    
Net operating loss carryforwards expiration, beginning year 2036    
Net operating loss carryforwards expiration, ending year 2038    
Tax periods open for examination Tax years ended December 31, 2012 through December 31, 2017    
Canada | Earliest Tax Year      
Income Taxes [Line Items]      
Tax period open for examination 2012    
Canada | Latest Tax Year      
Income Taxes [Line Items]      
Tax period open for examination 2017    
U.S.      
Income Taxes [Line Items]      
Net operating loss carryforwards expiration, beginning year 2034    
Net operating loss carryforwards expiration, ending year 2037    
Tax periods open for examination Tax years ended December 31, 2013 through December 31, 2017    
U.S. | Earliest Tax Year      
Income Taxes [Line Items]      
Tax period open for examination 2013    
U.S. | Latest Tax Year      
Income Taxes [Line Items]      
Tax period open for examination 2017