Employee Benefits and Share-Based Compensation - Assumptions Used to Value Stock Options Granted (Details) - Stock Options - 2009 Plan	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	4 years 10 months 24 days	4 years 8 months 12 days
Expected volatility	31.50%	39.40%
Risk-free interest rate	0.90%	0.70%
Estimated forfeiture rate	7.90%	5.70%
Dividend yield	0.00%	0.00%