Pending Merger (Details) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($) $ / shares	Jun. 30, 2026 USD ($) $ / shares
Business Combination [Line Items]
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Northwestern Energy Group Inc.
Business Combination [Line Items]
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Business Acquisition Share Conversion Ratio	0.98	0.98
Merger transaction costs \| $	$ 3.3	$ 6.7

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details