Acquisitions and divestitures - (Details 2) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
Aug. 13, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
|---|---|---|---|---|---|
| Identifiable assets acquired | |||||
| Cash and cash equivalents | $ 7,372 | $ 4,953 | $ 3,609 | $ 4,736 | |
| Property, plant, and equipment | $ 43,625 | $ 39,984 | $ 48,396 | ||
| Alianca Energia [Member] | |||||
| Identifiable assets acquired | |||||
| Cash and cash equivalents | $ 95 | ||||
| Intangibles | 828 | ||||
| Property, plant, and equipment | 573 | ||||
| Other | 40 | ||||
| Total Identifiable assets acquired | 1,536 | ||||
| Liabilities assumed | |||||
| Loans and borrowings | 245 | ||||
| Deferred income taxes | 312 | ||||
| Other | 140 | ||||
| Total Liabilities assumed | 697 | ||||
| Net assets acquired | 839 | ||||
| Consideration transferred for acquisition of the 45% equity interest held by Cemig GT | 493 | ||||
| Fair value of the 55% stake previously held by Vale | 603 | ||||
| Total [A] | 1,096 | ||||
| Fair value of net assets acquired | 1,096 | ||||
| (-) Deferred tax liability on the difference between the fair value and the book value of net assets | (257) | ||||
| Total net assets [B] | 839 | ||||
| Goodwill [A-B] | $ 257 |