Fair Value Measurements - Schedule of Investments in Debt Securities Held by Decommissioning Trust Fund (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Fair Value Measurements | ||||
| Purchases | $ 198 | $ 0 | $ 12,406 | $ 0 |
| Net Proceeds | 25 | 0 | (579) | 0 |
| Unrealized Gain (Loss) | 22 | 0 | 131 | 0 |
| Debt securities | ||||
| Fair Value Measurements | ||||
| Purchases | 198 | 0 | 12,406 | 0 |
| Net Proceeds | 0 | 0 | 0 | 0 |
| Unrealized Gain (Loss) | 22 | 0 | 131 | 0 |
| Cash and cash equivalents | ||||
| Fair Value Measurements | ||||
| Purchases | 0 | 0 | 0 | 0 |
| Net Proceeds | 2 | 0 | (745) | 0 |
| Unrealized Gain (Loss) | 0 | 0 | 0 | 0 |
| Other | ||||
| Fair Value Measurements | ||||
| Purchases | 0 | 0 | 0 | 0 |
| Net Proceeds | 23 | 0 | 166 | 0 |
| Unrealized Gain (Loss) | $ 0 | $ 0 | $ 0 | $ 0 |