Debt Covenant, Funded Debt To Total Capitalization, Ratio

No definition available.

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- Definition

Total Debt To Total Capitalization, Ratio

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

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.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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Debt - Narrative (Details) - USD ($) $ in Thousands				1 Months Ended		6 Months Ended
Debt - Narrative (Details) - USD ($) $ in Thousands	Aug. 18, 2026	Feb. 02, 2026	Oct. 28, 2025	Mar. 31, 2026	Feb. 28, 2026	Jun. 30, 2026	Jun. 30, 2025	Jan. 15, 2026	Dec. 31, 2025	Dec. 30, 2025
Line of Credit Facility [Line Items]
Repayments of long-term debt						$ 234,009	$ 111,008
Revolving Credit Facility \| Montana-Dakota Utilities Co.
Line of Credit Facility [Line Items]
Ratio of total debt to total capitalization						6500.00%
Senior Notes
Line of Credit Facility [Line Items]
Long-term debt, gross						$ 2,110,000	$ 1,947,000		$ 2,010,000
Senior Notes \| Montana-Dakota Utilities Co.
Line of Credit Facility [Line Items]
Ratio of total debt to total capitalization			65.00%
Debt instrument, face amount			$ 250,000
Interest rate, stated percentage			5.96%
Notes issued		$ 100,000	$ 150,000
Senior Notes \| Montana-Dakota Utilities Co. \| Forecast
Line of Credit Facility [Line Items]
Ratio of total debt to total capitalization	65.00%
Debt instrument, face amount	$ 225,000
Interest rate, stated percentage	6.17%
Notes issued	$ 225,000
Term Loan Agreement \| Montana-Dakota Utilities Co.
Line of Credit Facility [Line Items]
Ratio of total debt to total capitalization										65.00%
Debt instrument, face amount										$ 250,000
Repayments of long-term debt				$ 80,000	$ 100,000
Uncommitted Note Purchase And Private Shelf Agreement \| WBI Energy Transmission
Line of Credit Facility [Line Items]
Facility Limit								$ 350,000
Long-term debt, gross								235,000
Line of credit facility, remaining borrowing capacity								$ 115,000
Total debt to total capitalization						39.00%