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v3.21.1

Business Segment Information: Information Relating to Segment Statement of Income (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Segment Reporting Information |  |
Revenue from contracts with customers | $ 630,217 | $ 530,209
Revenues | 633,432 | 537,050
Operating income | 138,315 | 153,185
Interest expense, net | (37,600) | (35,453)
Impairment of investment | 0 | (6,859)
Other income (expense), net | 266 | 2,353
Income tax (expense) | (494) | (16,002)
Net income | 100,487 | 97,224
Net income attributable to noncontrolling interest | (4,171) | (4,050)
Net income available for common stock | 96,316 | 93,174
Inter-company Revenues |  |
Segment Reporting Information |  |
Revenue from contracts with customers | (39,848) | (38,642)
Revenues | (40,330) | (39,033)
Consolidation, Eliminations |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 0 | 0
Corporate |  |
Segment Reporting Information |  |
Operating income | (3,122) | 160
Electric Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 227,271 | 173,916
Revenues | 227,408 | 174,139
Operating income | 21,813 | 35,650
Gas Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 400,019 | 355,065
Revenues | 402,519 | 360,773
Operating income | 102,094 | 102,897
Power Generation |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 28,692 | 25,467
Revenues | 29,163 | 25,966
Operating income | 14,269 | 11,349
Mining |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 14,083 | 14,403
Revenues | 14,672 | 15,205
Operating income | 3,261 | 3,129
Other Revenues |  |
Segment Reporting Information |  |
Revenues | 3,215 | 6,841
Other Revenues | Inter-company Revenues |  |
Segment Reporting Information |  |
Revenues | (482) | (391)
Other Revenues | Consolidation, Eliminations |  |
Segment Reporting Information |  |
Revenues | 0 | 0
Other Revenues | Electric Utilities |  |
Segment Reporting Information |  |
Revenues | 137 | 223
Other Revenues | Gas Utilities |  |
Segment Reporting Information |  |
Revenues | 2,500 | 5,708
Other Revenues | Power Generation |  |
Segment Reporting Information |  |
Revenues | 471 | 499
Other Revenues | Mining |  |
Segment Reporting Information |  |
Revenues | 589 | 802
External Operating Revenue |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 630,217 | 530,209
External Operating Revenue | Electric Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 220,500 | 167,503
External Operating Revenue | Gas Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 398,499 | 354,287
External Operating Revenue | Power Generation |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 4,241 | 1,855
External Operating Revenue | Mining |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 6,977 | 6,564
External Operating Revenue | Other Revenues |  |
Segment Reporting Information |  |
Revenues | 3,215 | 6,841
External Operating Revenue | Other Revenues | Electric Utilities |  |
Segment Reporting Information |  |
Revenues | 137 | 223
External Operating Revenue | Other Revenues | Gas Utilities |  |
Segment Reporting Information |  |
Revenues | 2,408 | 5,708
External Operating Revenue | Other Revenues | Power Generation |  |
Segment Reporting Information |  |
Revenues | 421 | 443
External Operating Revenue | Other Revenues | Mining |  |
Segment Reporting Information |  |
Revenues | 249 | 467
Inter-company Operating Revenue | Electric Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 6,771 | 6,413
Inter-company Operating Revenue | Gas Utilities |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 1,520 | 778
Inter-company Operating Revenue | Power Generation |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 24,451 | 23,612
Inter-company Operating Revenue | Mining |  |
Segment Reporting Information |  |
Revenue from contracts with customers | 7,106 | 7,839
Inter-company Operating Revenue | Other Revenues | Electric Utilities |  |
Segment Reporting Information |  |
Revenues | 0 | 0
Inter-company Operating Revenue | Other Revenues | Gas Utilities |  |
Segment Reporting Information |  |
Revenues | 92 | 0
Inter-company Operating Revenue | Other Revenues | Power Generation |  |
Segment Reporting Information |  |
Revenues | 50 | 56
Inter-company Operating Revenue | Other Revenues | Mining |  |
Segment Reporting Information |  |
Revenues | $ 340 | $ 335

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