Income Taxes - Schedule of Income Tax Expense Reconciled to Tax Computed at Statutory Rates (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 22, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Federal Income Taxes		$ 906	$ 904	$ 1,100
State Income Taxes		108	112	102
Deferred Tax Rate Change	$ (3,500)	0	0	(3,506)
Other		(29)	(21)	(25)
Income Tax Expense		$ 985	$ 995	$ (2,329)
Percent
Federal Income Taxes		21.00%	21.00%	35.00%
State Income Taxes		2.50%	2.60%	3.20%
Deferred Tax Rate Change		0.00%	0.00%	(111.60%)
Other		(0.70%)	(0.50%)	(0.80%)
Income Tax Rate		22.80%	23.10%	(74.20%)