Quarterly report pursuant to Section 13 or 15(d)

Income Taxes - Additional Information (Details)

v3.8.0.1
Income Taxes - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Jan. 01, 2018
Dec. 31, 2017
Schedule Of Income Taxes [Line Items]        
Effective income tax rate reconciliation (percent) (2.80%) 9.00%    
Excess tax benefit $ 4,200 $ 2,700    
Cumulative effect of adoption of ASU 2014-09       $ 2,221
Difference between Revenue Guidance in Effect before and after Topic 606 | Adjustments due to ASU 2014-09        
Schedule Of Income Taxes [Line Items]        
Deferred income tax liabilities     $ (800)  
Accumulated Deficit        
Schedule Of Income Taxes [Line Items]        
Cumulative effect of adoption of ASU 2014-09       2,221
Accumulated Deficit | Adjustments due to ASU 2014-09        
Schedule Of Income Taxes [Line Items]        
Cumulative effect of adoption of ASU 2014-09       $ 2,200
Accumulated Deficit | Difference between Revenue Guidance in Effect before and after Topic 606 | Adjustments due to ASU 2014-09        
Schedule Of Income Taxes [Line Items]        
Cumulative effect of adoption of ASU 2014-09     $ 800