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Pending Business Combination - Additional Information (Details)	Sep. 30, 2025 $ / shares	Aug. 18, 2025 $ / shares	Dec. 31, 2024 $ / shares
Business Combination [Line Items]
Common stock, par value (usd per share)	$ 1		$ 1
NorthWestern
Business Combination [Line Items]
Common stock, par value (usd per share)		$ 0.01
Business acquisition exchange ratio on common stock		0.98
Business acquisition exchange of common stock par value per share		$ 1

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