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Business Segment Information: Capital Expenditures and Asset Acquisitions (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Segment Reporting Information [Line Items] |  |  |
Capital Expenditures | $ 679,590 | $ 755,392 | $ 849,755
Corporate, Non-Segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Capital Expenditures | 10,500 | 17,500 | 20,702
Electric Utilities |  |  |
Segment Reporting Information [Line Items] |  |  |
Capital Expenditures | 285,770 | 288,683 | 316,687
Gas Utilities |  |  |
Segment Reporting Information [Line Items] |  |  |
Capital Expenditures | $ 383,320 | $ 449,209 | $ 512,366

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- 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. + References No definition available. + 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 No definition available. + Details
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- Details
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- Details
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- Details
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