Annual report pursuant to Section 13 and 15(d)

Employee Benefits and Share-Based Compensation - Summary of Assumptions Used within Option-Pricing Model (Details)

v3.20.4
Employee Benefits and Share-Based Compensation - Summary of Assumptions Used within Option-Pricing Model (Details) - Performance-Based Option Awards
12 Months Ended
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected share price volatility, minimum 31.50%
Expected share price volatility, maximum 32.20%
Risk-free interest rate, minimum 2.48%
Risk-free interest rate, maximum 2.58%
Minimum  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected term 3 years 8 months 19 days
Maximum  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected term 4 years 2 months 19 days