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Stock-Based Compensation Plans - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense $ 14,372 $ 7,705 $ 20,957 $ 14,067
Stock-based compensation expense, tax benefits 2,800 $ 1,200 4,000 $ 2,200
Stock Options        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Incentive plan, weighted average grant date fair value of stock options granted (in dollars per share)       $ 7.03
Incentive plan, total intrinsic value of stock options exercised     6,000 $ 11,300
Unrecognized compensation costs 800   $ 800  
Unrecognized compensation costs, weighted average recognition period     8 months 12 days  
LTIP Performance Shares        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense, additional expense due to changes in expected attainment rates 6,000   $ 6,000  
Unrecognized compensation costs 3,800   $ 3,800  
Unrecognized compensation costs, weighted average recognition period     8 months 12 days  
Restricted Share Awards (RSAs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares vested     104,763  
Shares withheld to pay employees' portion of minimum payroll withholding taxes     32,371  
Unrecognized compensation costs 1,300   $ 1,300  
Unrecognized compensation costs, weighted average recognition period     8 months 12 days  
Total Shareholder Return Awards (TSRs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation costs 27,400   $ 27,400  
Unrecognized compensation costs, weighted average recognition period     2 years 1 month 6 days  
Restricted Share Units (RSUs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares vested     257,982  
Shares withheld to pay employees' portion of minimum payroll withholding taxes     57,403  
Unrecognized compensation costs $ 27,400   $ 27,400  
Unrecognized compensation costs, weighted average recognition period     1 year 9 months 18 days  
Employee Stock Purchase Plan 2017        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares issued under ESPP     60,362 77,118