Fair Value Measurements - Schedule of Fair Value of Derivative Assets and Liabilities and Effect of Counterparty Netting (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Assets
Total Fair Value of Gross Assets & Liabilities	$ 9,936	$ 2,974
Effect of Counterparty Netting	(8,997)	(2,670)
Effect of Collateral Netting	(160)	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	779	304
Liabilities
Total fair value gross liabilities	28,771	21,435
Effect of Counterparty Netting	(8,997)	(2,670)
Effect of Collateral Netting	(12)	(20)
Difference in Carrying Value and Fair Value	732	621
Net Carrying Value Presented on the Balance Sheet	20,494	19,366
Level 1
Assets
Total Fair Value of Gross Assets & Liabilities	9,587	2,901
Liabilities
Total fair value gross liabilities	8,980	2,680
Level 2
Assets
Total Fair Value of Gross Assets & Liabilities	342	69
Liabilities
Total fair value gross liabilities	19,786	18,754
Level 3
Assets
Total Fair Value of Gross Assets & Liabilities	7	4
Liabilities
Total fair value gross liabilities	5	1
Rabbi trust assets
Assets
Investments in rabbi trust assets and in NOVONIX	127	144
Difference in Carrying Value and Fair Value	0	0
Rabbi trust assets \| Level 1
Assets
Investments in rabbi trust assets and in NOVONIX	127	144
Rabbi trust assets \| Level 2
Assets
Investments in rabbi trust assets and in NOVONIX	0	0
Rabbi trust assets \| Level 3
Assets
Investments in rabbi trust assets and in NOVONIX	0	0
Investment in NOVONIX
Assets
Investments in rabbi trust assets and in NOVONIX	9	26
Difference in Carrying Value and Fair Value	0	0
Investment in NOVONIX \| Level 1
Assets
Investments in rabbi trust assets and in NOVONIX	9	26
Investment in NOVONIX \| Level 2
Assets
Investments in rabbi trust assets and in NOVONIX	0	0
Investment in NOVONIX \| Level 3
Assets
Investments in rabbi trust assets and in NOVONIX	0	0
Floating-rate debt
Liabilities
Debt	1,249	400
Difference in Carrying Value and Fair Value	0	0
Floating-rate debt \| Net Carrying Value Presented on the Balance Sheet
Liabilities
Debt	1,249	400
Floating-rate debt \| Level 1
Liabilities
Debt	0	0
Floating-rate debt \| Level 2
Liabilities
Debt	1,249	400
Floating-rate debt \| Level 3
Liabilities
Debt	0	0
Fixed-rate debt, excluding finance leases and software obligations
Liabilities
Debt	18,118	18,324
Difference in Carrying Value and Fair Value	732	621
Fixed-rate debt, excluding finance leases and software obligations \| Net Carrying Value Presented on the Balance Sheet
Liabilities
Debt	18,850	18,945
Fixed-rate debt, excluding finance leases and software obligations \| Level 1
Liabilities
Debt	0	0
Fixed-rate debt, excluding finance leases and software obligations \| Level 2
Liabilities
Debt	18,118	18,324
Fixed-rate debt, excluding finance leases and software obligations \| Level 3
Liabilities
Debt	0	0
Commodity derivatives \| Exchange-cleared instruments
Assets
Commodity Derivative Assets	9,451	2,731
Effect of Counterparty Netting	(8,963)	(2,660)
Effect of Collateral Netting	(160)	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	328	71
Liabilities
Commodity Derivative Liabilities	8,980	2,680
Effect of Counterparty Netting	(8,963)	(2,660)
Effect of Collateral Netting	(12)	(20)
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	5	0
Commodity derivatives \| Physical forward contracts
Assets
Commodity Derivative Assets	349	73
Effect of Counterparty Netting	(34)	(10)
Effect of Collateral Netting	0	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	315	63
Liabilities
Commodity Derivative Liabilities	424	31
Effect of Counterparty Netting	(34)	(10)
Effect of Collateral Netting	0	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	390	21
Commodity derivatives \| Level 1 \| Exchange-cleared instruments
Assets
Commodity Derivative Assets	9,451	2,731
Liabilities
Commodity Derivative Liabilities	8,980	2,680
Commodity derivatives \| Level 1 \| Physical forward contracts
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Commodity derivatives \| Level 2 \| Exchange-cleared instruments
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Commodity derivatives \| Level 2 \| Physical forward contracts
Assets
Commodity Derivative Assets	342	69
Liabilities
Commodity Derivative Liabilities	419	30
Commodity derivatives \| Level 3 \| Exchange-cleared instruments
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Commodity derivatives \| Level 3 \| Physical forward contracts
Assets
Commodity Derivative Assets	7	4
Liabilities
Commodity Derivative Liabilities	$ 5	$ 1

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