Income Taxes - Reconciliation of Federal Statutory Tax to Total Provisions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Statutory rate applied to earnings (loss) before income taxes	$ 912	$ (275)	$ (95)
Valuation allowance	(633)	367	334
Tax accounting benefit related to increase in OCI	0	(138)	0
Excess percentage depletion	(66)	(31)	(46)
Capital loss generated	(139)	0	0
State and local income taxes after federal income tax effects	83	(47)	(36)
Effects of foreign operations	191	(10)	(23)
U.S. impact of foreign operations	4	1	25
Impact of tax credits	(173)	(18)	5
Adjustment of prior years' federal income taxes	(5)	12	7
Other	(4)	(3)	7
Total provision (benefit)	$ 170	$ (142)	$ 178

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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