The average market price for a group of price risk forward or futures contracts, such as gas futures contracts.

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

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- Definition

The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal mass used to calculate payments on a derivative instrument.

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Financial Instruments - Unrealized gains losses (Details) oz in Thousands, lb in Millions, $ in Millions		3 Months Ended		9 Months Ended
	Jun. 30, 2023 oz lb	Sep. 30, 2026 USD ($) $ / oz $ / lb $ / lb	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) lb $ / oz $ / lb $ / lb	Sep. 30, 2025 USD ($)
Commodity Contract
Unrealized gains (losses):
Derivative financial instruments		$ 0	$ (23)	$ (19)	$ 44
Hedged item – firm sales commitments		0	23	19	(44)
Realized gains (losses):
Matured derivative financial instruments		46	1	119	31
Matured derivative financial instruments		$ 46	1	$ 119	31
Commodity Contract \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb				133
Derivative, Average Forward Price \| $ / lb		6.30		6.30
Forward Contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb				2
Derivative, Average Forward Price \| $ / lb		6.64		6.64
Realized gains (losses):
Matured derivative financial instruments		$ (15)	(7)	$ (50)	(47)
Matured derivative financial instruments		(15)	(7)	(50)	(47)
Copper \| Not Designated as Hedging Instrument
Realized gains (losses):
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net		$ 116	82	$ 232	232
Copper \| Short [Member] \| Embedded Derivative Financial Instruments \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	256
Derivative, Average Forward Price \| $ / lb		6.34		6.34
Realized gains (losses):
Derivative Average Market Price \| $ / lb		6.55		6.55
Copper \| Long [Member] \| Embedded Derivative Financial Instruments \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	191
Derivative, Average Forward Price \| $ / lb		6.35		6.35
Realized gains (losses):
Derivative Average Market Price \| $ / lb		6.55		6.55
Gold \| Short [Member] \| Embedded Derivative Financial Instruments \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| oz	2
Derivative, Average Forward Price \| $ / oz		4,319		4,319
Realized gains (losses):
Derivative Average Market Price \| $ / oz		4,226		4,226
gold and other \| Not Designated as Hedging Instrument
Realized gains (losses):
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net		$ 5	$ 71	$ (19)	$ 131