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Fair Value Measurements - Schedule of Investments in Debt Securities Held by Decommissioning Trust Fund (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fair Value Measurements
Purchases	$ 245	$ 0	$ 12,651	$ 0
Net Proceeds	(20)	0	(599)	0
Unrealized Gain (Loss)	43	0	174	0
Debt securities
Fair Value Measurements
Purchases	245	0	12,651	0
Net Proceeds	0	0	0	0
Unrealized Gain (Loss)	43	0	174	0
Cash and cash equivalents
Fair Value Measurements
Purchases	0	0	0	0
Net Proceeds	(3)	0	(748)	0
Unrealized Gain (Loss)	0	0	0	0
Other
Fair Value Measurements
Purchases	0	0	0	0
Net Proceeds	(17)	0	149	0
Unrealized Gain (Loss)	$ 0	$ 0	$ 0	$ 0

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+ References

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- Definition

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

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