Statement Of Financial Position [Abstract]

Fortum Oyj - Filing #3292332

Concept	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2024-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2023-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31	As at 2022-12-31
Statement of financial position [abstract]
Assets [abstract]
Investments accounted for using equity method	—	—	—	—	—	—	—	—	1 260 EUR	—	1 059 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Deferred tax assets	—	—	—	—	—	—	—	—	845,000,000 EUR	—	958,000,000 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Cash and cash equivalents	—	—	—	—	—	—	—	—	4 136 EUR	—	4 183 EUR	—	—	—	—	—	—	—	—	—	3 919 EUR	—	—	—	—	—	—	—	—	—
Assets	—	—	—	—	—	—	—	—	17 307 EUR	—	18 739 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Equity and liabilities [abstract]
Equity [abstract]
Issued capital	—	—	—	—	—	—	—	—	3 046 EUR	—	3 046 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Retained earnings	—	—	—	—	—	—	—	—	5 770 EUR	—	5 592 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Share premium	—	—	—	—	—	—	—	—	73,000,000 EUR	—	73,000,000 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Other equity interest	—	—	—	—	—	—	—	—	186,000,000 EUR	—	273,000,000 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Equity attributable to owners of parent	—	—	—	—	—	—	—	—	9 074 EUR	—	8 438 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Non-controlling interests	—	—	—	—	—	—	—	—	79,000,000 EUR	—	60,000,000 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Equity	73,000,000 EUR	53,000,000 EUR	6 780 EUR	3 046 EUR	79,000,000 EUR	1 010 EUR	9 074 EUR	127,000,000 EUR	9 154 EUR	5,000,000 EUR	8 499 EUR	6 618 EUR	79,000,000 EUR	60,000,000 EUR	73,000,000 EUR	3 046 EUR	1 026 EUR	8 438 EUR	337,000,000 EUR	14,000,000 EUR	7 737 EUR	93,000,000 EUR	9 499 EUR	67,000,000 EUR	73,000,000 EUR	172,000,000 EUR	3 046 EUR	3 031 EUR	7 670 EUR	2 182 EUR
Liabilities [abstract]
Deferred tax liabilities	—	—	—	—	—	—	—	—	386,000,000 EUR	—	428,000,000 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Liabilities	—	—	—	—	—	—	—	—	8 153 EUR	—	10 240 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Equity and liabilities	—	—	—	—	—	—	—	—	17 307 EUR	—	18 739 EUR	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—