Income Taxes - Income Tax Expense Reconciled to Tax Computed at Statutory Rates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Expense
Federal Income Taxes	$ 1,027	$ 1,137	$ 1,040
State Income Taxes	153	121	139
Other	(4)	(10)	(9)
Total Income Tax Expense	$ 1,176	$ 1,248	$ 1,170
Rate
Federal Income Taxes	21.00%	21.00%	21.00%
State Income Taxes	3.10%	2.20%	2.80%
Other	(0.10%)	(0.10%)	(0.20%)
Income Tax Rate	24.00%	23.10%	23.60%