Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Allowance for doubtful accounts receivable
Reserves and allowances deducted from asset accounts
Balance at the beginning of the period	$ 2	$ 2
Charge to cost and expenses	0	0	$ 0
Charge to other accounts			2
Balance at the end of the period	2	2	2
Allowance for obsolete materials and supplies
Reserves and allowances deducted from asset accounts
Balance at the beginning of the period	183	143	127
Charge to cost and expenses	16	43	25
Deductions		3	9
Balance at the end of the period	199	183	143
Valuation allowance on deferred tax assets
Reserves and allowances deducted from asset accounts
Balance at the beginning of the period	1,820	685	716
Charge to cost and expenses	79	1,167	(31)
Charge to other accounts	11
Deductions		32
Balance at the end of the period	$ 1,910	$ 1,820	$ 685