Fair Value of Financial Instruments - Assets and Liabilities Measured and Recorded at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in securities (classified within other current and non-current assets)	$ 21	$ 19
Other trust fund investments (classified within other non-current assets):
Other trust fund investments		1
Measured using net asset value practical expedient:
Total assets	6,182	12,858
Derivative liabilities:
Total liabilities	5,507	8,441
Interest rate contracts
Derivative assets:
Derivative Assets	12
Derivative liabilities:
Derivative liabilities	8
Foreign exchange contract
Derivative assets:
Derivative Assets	5	18
Derivative liabilities:
Derivative liabilities	9	2
Commodity contracts
Derivative assets:
Derivative Assets	6,138	11,976
Derivative liabilities:
Derivative liabilities	5,356	8,439
Consumer Financing Program
Derivative liabilities:
Derivative liabilities	134
Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments		15
U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments		86
Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		101
Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		35
Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments		114
Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments		403
Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments		1
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	0
Other trust fund investments (classified within other non-current assets):
Other trust fund investments		1
Measured using net asset value practical expedient:
Total assets	1,334	2,432
Derivative liabilities:
Total liabilities	1,413	1,244
Level 1 \| Interest rate contracts
Derivative assets:
Derivative Assets	0
Derivative liabilities:
Derivative liabilities	0
Level 1 \| Foreign exchange contract
Derivative assets:
Derivative Assets	0	0
Derivative liabilities:
Derivative liabilities	0	0
Level 1 \| Commodity contracts
Derivative assets:
Derivative Assets	1,334	1,929
Derivative liabilities:
Derivative liabilities	1,413	1,244
Level 1 \| Consumer Financing Program
Derivative liabilities:
Derivative liabilities	0
Level 1 \| Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments		15
Level 1 \| U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments		84
Level 1 \| Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 1 \| Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 1 \| Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 1 \| Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments		403
Level 1 \| Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments		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)	21	19
Other trust fund investments (classified within other non-current assets):
Other trust fund investments		0
Measured using net asset value practical expedient:
Total assets	4,508	9,086
Derivative liabilities:
Total liabilities	3,745	6,451
Level 2 \| Interest rate contracts
Derivative assets:
Derivative Assets	12
Derivative liabilities:
Derivative liabilities	8
Level 2 \| Foreign exchange contract
Derivative assets:
Derivative Assets	5	18
Derivative liabilities:
Derivative liabilities	9	2
Level 2 \| Commodity contracts
Derivative assets:
Derivative Assets	4,470	8,796
Derivative liabilities:
Derivative liabilities	3,728	6,449
Level 2 \| Consumer Financing Program
Derivative liabilities:
Derivative liabilities	0
Level 2 \| Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 2 \| U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments		2
Level 2 \| Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		101
Level 2 \| Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		35
Level 2 \| Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments		114
Level 2 \| Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 2 \| Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments		1
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):
Other trust fund investments		0
Measured using net asset value practical expedient:
Total assets	334	1,251
Derivative liabilities:
Total liabilities	349	746
Level 3 \| Interest rate contracts
Derivative assets:
Derivative Assets	0
Derivative liabilities:
Derivative liabilities	0
Level 3 \| Foreign exchange contract
Derivative assets:
Derivative Assets	0	0
Derivative liabilities:
Derivative liabilities	0	0
Level 3 \| Commodity contracts
Derivative assets:
Derivative Assets	334	1,251
Derivative liabilities:
Derivative liabilities	215	746
Level 3 \| Consumer Financing Program
Derivative liabilities:
Derivative liabilities	134
Level 3 \| Cash and cash equivalents
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| U.S. government and federal agency obligations
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| Federal agency mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| Commercial mortgage-backed securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| Corporate debt securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| Equity securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Level 3 \| Foreign government fixed income securities
Nuclear trust fund investments:
Nuclear trust fund investments		0
Net Asset Value \| Equity securities
Measured using net asset value practical expedient:
Equity securities	$ 6	6
Net Asset Value \| Equity securities - nuclear trust fund investments
Measured using net asset value practical expedient:
Equity securities		$ 83

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Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled.

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