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Stock-based Compensation - Additional Information (Details)
$ in Millions
3 Months Ended
Mar. 31, 2017
USD ($)
shares
Incentive Plan 2005  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares reserved for issuance 27,783,379
Number of shares available for issuance 6,982,718
Employee Stock Purchase Plan 2010  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Maximum number of shares available 2,400,000
Number of shares remaining 821,770
Restricted Stock Units (RSUs)  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Total unamortized compensation cost | $ $ 86.9
Weighted average period of total unamortized cost (in years) 2 years 7 months 6 days
Market Performance Based Restricted Stock Units  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Total unamortized compensation cost | $ $ 19.4
Weighted average period of total unamortized cost (in years) 1 year 8 months 12 days
Market Performance Based Restricted Stock Units | Minimum  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Vesting period of granted market-performance based restricted stock units 2 years
Market Performance Based Restricted Stock Units | Maximum  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Vesting period of granted market-performance based restricted stock units 3 years
Percentage of market-performance based restricted stock units eligible to vest over the vesting period 200.00%
Employee Stock Purchase Plan  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Total unamortized compensation cost | $ $ 3.9
Weighted average period of total unamortized cost (in years) 1 year