Income Taxes - Schedule of Reconciliation of U.S. Federal statutory Income Tax Rate to Effective Income Tax Rate on Earnings (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory U.S. federal income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	5.10%	5.70%	6.40%
Reserve adjustments	0.70%	2.00%	1.40%
Tax credits and special deductions	(2.60%)	(1.40%)	(2.00%)
Nondeductible compensation	1.90%	0.50%	0.50%
Stock-based compensation excess tax benefits	(2.40%)	(1.20%)	(0.20%)
Other	(0.10%)	(0.10%)	0.10%
Effective income tax rate	23.60%	26.50%	27.20%