Earnings per share (Details) - CHF (SFr) SFr / shares in Units, SFr in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Earnings per share [line items] | ||||
| Net income / (loss) | SFr 105.0 | SFr (40.9) | SFr 208.3 | SFr 15.8 |
| Class A | ||||
| Earnings per share [line items] | ||||
| Weighted number of outstanding shares (in shares) | 300,422,597 | 295,531,210 | 298,951,784 | 294,458,484 |
| Weighted number of shares with dilutive effects (in shares) | 1,677,255 | 3,300,452 | 2,596,588 | 4,005,446 |
| Weighted number of outstanding shares (diluted and undiluted) (in shares) | 302,099,852 | 298,831,661 | 301,548,372 | 298,463,930 |
| Net income / (loss) | SFr 94.5 | SFr (36.7) | SFr 187.1 | SFr 14.1 |
| Basic EPS (CHF) (in CHF per share) | SFr 0.31 | SFr (0.12) | SFr 0.63 | SFr 0.05 |
| Diluted EPS (CHF) (in CHF per share) | SFr 0.31 | SFr (0.12) | SFr 0.62 | SFr 0.05 |
| Class B | ||||
| Earnings per share [line items] | ||||
| Weighted number of outstanding shares (in shares) | 335,348,823 | 341,044,191 | 338,278,973 | 343,228,709 |
| Weighted number of shares with dilutive effects (in shares) | 2,493,692 | 12,293,550 | 3,726,415 | 12,885,677 |
| Weighted number of outstanding shares (diluted and undiluted) (in shares) | 337,842,515 | 353,337,741 | 342,005,388 | 356,114,386 |
| Net income / (loss) | SFr 10.5 | SFr (4.2) | SFr 21.2 | SFr 1.6 |
| Basic EPS (CHF) (in CHF per share) | SFr 0.03 | SFr (0.01) | SFr 0.06 | SFr 0 |
| Diluted EPS (CHF) (in CHF per share) | SFr 0.03 | SFr (0.01) | SFr 0.06 | SFr 0 |