Investments in Affiliated Companies - Current Year And Cumulative Gains/Losses (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
|
| Investments in and Advances to Affiliates [Abstract] | |||||
| Equity Securities, FV-NI, Realized Gain | $ 0.3 | $ 12.3 | $ 19.2 | $ 12.3 | |
| Equity Securities, FV-NI, Realized Loss | 0.0 | $ (5.3) | (11.7) | $ (15.7) | |
| Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Cumulative Amount | 46.3 | 46.3 | $ 50.8 | ||
| Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment, Cumulative Amount | $ (41.4) | $ (41.4) | $ (35.0) | ||