Income Taxes - Federal Statutory Tax Rate and Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax expense at statutory rate	$ 326	$ 246	$ 210
State income taxes, net of federal benefit	55	39	32
U.S. tax expense (benefit) on undistributed non-U.S. earnings	6	(2)	6
Non-U.S. tax expense on non-U.S. earnings	8	5	4
Reserve for uncertain tax positions	(10)	0	(3)
Other tax expense (benefit)	3	5	(3)
Research credits	(20)	(28)	(10)
Stock compensation	(32)	(48)	(27)
Valuation allowances	(34)	4	(79)
Total income tax expense	$ 302	$ 221	$ 130
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax expense at statutory rate	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	3.50%	3.30%	3.20%
U.S. tax expense (benefit) on undistributed non-U.S. earnings	0.40%	(0.20%)	0.60%
Non-U.S. tax expense on non-U.S. earnings	0.50%	0.50%	0.40%
Reserve for uncertain tax positions	(0.60%)	0.00%	(0.30%)
Other tax expense (benefit)	0.20%	0.40%	(0.30%)
Research credits	(1.30%)	(2.40%)	(1.00%)
Stock compensation	(2.10%)	(4.10%)	(2.70%)
Valuation allowances	(2.20%)	0.30%	(7.90%)
Total income tax expense (benefit), percent	19.50%	18.80%	13.00%