Fair Value of Financial Instruments - Assets and Liabilities Measured and Recorded at Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in securities (classified within other current and non-current assets)	$ 19	$ 32
Other trust fund investments (classified within other non-current assets):
U.S. government and federal agency obligations	1	1
Measured using net asset value practical expedient:
Total assets	15,667	8,188
Derivative liabilities:
Commodity contracts	9,643	4,799
Foreign exchange contract
Derivative assets:
Derivative contracts	30	1
Derivative liabilities:
Commodity contracts		1
Commodity contracts
Derivative assets:
Derivative contracts	14,822	7,139
Derivative liabilities:
Commodity contracts	9,643	4,798
Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments	17	33
U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments	85	112
Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	101	100
Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	37	44
Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments	104	122
Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments	372	494
Measured using net asset value practical expedient:
Equity securities	6	7
Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments	2	4
Equity securities — nuclear trust fund investments
Measured using net asset value practical expedient:
Equity securities	71	99
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in securities (classified within other current and non-current assets)	0	15
Other trust fund investments (classified within other non-current assets):
U.S. government and federal agency obligations	1	1
Measured using net asset value practical expedient:
Total assets	3,346	1,635
Derivative liabilities:
Commodity contracts	1,228	626
Level 1 | Foreign exchange contract
Derivative assets:
Derivative contracts	0	0
Derivative liabilities:
Commodity contracts		0
Level 1 | Commodity contracts
Derivative assets:
Derivative contracts	2,873	981
Derivative liabilities:
Commodity contracts	1,228	626
Level 1 | Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments	17	33
Level 1 | U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments	83	111
Level 1 | Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 1 | Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 1 | Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 1 | Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments	372	494
Level 1 | Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in securities (classified within other current and non-current assets)	19	17
Other trust fund investments (classified within other non-current assets):
U.S. government and federal agency obligations	0	0
Measured using net asset value practical expedient:
Total assets	11,231	5,990
Derivative liabilities:
Commodity contracts	8,084	4,009
Level 2 | Foreign exchange contract
Derivative assets:
Derivative contracts	30	1
Derivative liabilities:
Commodity contracts		1
Level 2 | Commodity contracts
Derivative assets:
Derivative contracts	10,936	5,701
Derivative liabilities:
Commodity contracts	8,084	4,008
Level 2 | Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 2 | U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments	2	1
Level 2 | Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	101	100
Level 2 | Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	37	44
Level 2 | Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments	104	122
Level 2 | Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 2 | Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments	2	4
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in securities (classified within other current and non-current assets)	0	0
Other trust fund investments (classified within other non-current assets):
U.S. government and federal agency obligations	0	0
Measured using net asset value practical expedient:
Total assets	1,013	457
Derivative liabilities:
Commodity contracts	331	164
Level 3 | Foreign exchange contract
Derivative assets:
Derivative contracts	0	0
Derivative liabilities:
Commodity contracts		0
Level 3 | Commodity contracts
Derivative assets:
Derivative contracts	1,013	457
Derivative liabilities:
Commodity contracts	331	164
Level 3 | Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments	0	0
Level 3 | Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments	$ 0	$ 0