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Business Segment Information: Capital Expenditures and Asset Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Capital Expenditures	$ 797.6	$ 589.9	$ 597.7
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Capital Expenditures	13.0	7.3	5.1
Electric Utilities | Operating Segments
Segment Reporting Information [Line Items]
Capital Expenditures	381.9	210.7	243.1
Gas Utilities | Operating Segments
Segment Reporting Information [Line Items]
Capital Expenditures	$ 402.7	$ 371.9	$ 349.5

X

- Definition

Amount of increase (decrease) of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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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

No definition available.

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