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Business Segment Information: Capital Expenditures and Asset Acquisitions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Capital Expenditures	$ 755,392	$ 849,755
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Capital Expenditures	17,500	20,702
Electric Utilities
Segment Reporting Information [Line Items]
Capital Expenditures	271,104	222,911
Gas Utilities
Segment Reporting Information [Line Items]
Capital Expenditures	449,209	512,366
Power Generation
Segment Reporting Information [Line Items]
Capital Expenditures	9,329	85,346
Mining
Segment Reporting Information [Line Items]
Capital Expenditures	$ 8,250	$ 8,430

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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