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v3.25.3

Financing: Debt Covenants (Additional Information) (Details) | Sep. 30, 2025
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Line of Credit Facility [Line Items] |
Consolidated indebtedness to capitalization ratio | 0.54
Maximum |
Line of Credit Facility [Line Items] |
Consolidated indebtedness to capitalization ratio | 0.65
Wyoming Electric |
Line of Credit Facility [Line Items] |
Consolidated indebtedness to capitalization ratio | 0.5
Wyoming Electric | Maximum |
Line of Credit Facility [Line Items] |
Consolidated indebtedness to capitalization ratio | 0.6

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