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Income Taxes - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Income Tax Examination [Line Items]      
Corporate income tax rate 21.00%   35.00%
Provisional income tax expense     $ 3,300
Income tax benefit $ 3,810 $ 944  
Gross liability for tax positions 3,700    
Change in unrecognized tax benefits reasonably possible $ 2,800    
Income tax examination years description The Company is no longer subject to U.S. Federal income tax examinations for the years prior to 2014.    
Interest and Penalties      
Income Tax Examination [Line Items]      
Gross liability for tax positions $ 1,000    
State Jurisdiction | Minimum      
Income Tax Examination [Line Items]      
Income tax examination year 2013    
State Jurisdiction | Maximum      
Income Tax Examination [Line Items]      
Income tax examination year 2017    
Domestic      
Income Tax Examination [Line Items]      
Effective income tax rate 24.60% 33.50%  
Foreign      
Income Tax Examination [Line Items]      
Effective income tax rate, change in enacted rate 0.00% 0.00%