Schedule of Segment Reporting Information, by Segment |
Segment information was as follows (in thousands): | | | | | | | | | | | | Total assets (net of intercompany eliminations) as of: | June 30, 2021 | | December 31, 2020 | Electric Utilities | $ | 3,239,628 | | | $ | 3,120,928 | | Gas Utilities | 4,935,784 | | | 4,376,204 | | Power Generation | 394,213 | | | 404,220 | | Mining | 75,109 | | | 77,085 | | Corporate and Other | 93,318 | | | 110,349 | | Total assets | $ | 8,738,052 | | | $ | 8,088,786 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Three Months Ended June 30, 2021 | External Operating Revenue | | Inter-company Operating Revenue | | Total Revenues | Contract Customers | Other Revenues | Contract Customers | Other Revenues | Segment: | | | | | | | | Electric Utilities | $ | 177,092 | | $ | 2,279 | | | $ | 5,562 | | $ | — | | | $ | 184,933 | | Gas Utilities | 183,187 | | 1,250 | | | 1,519 | | 94 | | | 186,050 | | Power Generation | 1,432 | | 386 | | | 23,480 | | 50 | | | 25,348 | | Mining | 6,712 | | 234 | | | 7,142 | | 341 | | | 14,429 | | Inter-company eliminations | — | | — | | | (37,703) | | (485) | | | (38,188) | | Total | $ | 368,423 | | $ | 4,149 | | | $ | — | | $ | — | | | $ | 372,572 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Three Months Ended June 30, 2020 | External Operating Revenue | | Inter-company Operating Revenue | | Total Revenues | Contract Customers | Other Revenues | Contract Customers | Other Revenues | Segment: | | | | | | | | Electric Utilities | $ | 156,197 | | $ | 1,627 | | | $ | 5,376 | | $ | — | | | $ | 163,200 | | Gas Utilities | 159,824 | | 512 | | | 774 | | — | | | 161,110 | | Power Generation | 1,242 | | 349 | | | 24,476 | | 55 | | | 26,122 | | Mining | 6,930 | | 233 | | | 7,916 | | 337 | | | 15,416 | | Inter-company eliminations | — | | — | | | (38,542) | | (392) | | | (38,934) | | Total | $ | 324,193 | | $ | 2,721 | | | $ | — | | $ | — | | | $ | 326,914 | |
| | | | | | | | | | | | | | | | | | | | | | | | Six Months Ended June 30, 2021 | External Operating Revenue | | Inter-company Operating Revenue | | Total Revenues | Contract Customers | Other Revenues | Contract Customers | Other Revenues | Segment: | | | | | | | | Electric Utilities | $ | 397,592 | | $ | 2,416 | | | $ | 12,333 | | $ | — | | | $ | 412,341 | | Gas Utilities | 581,686 | | 3,658 | | | 3,039 | | 186 | | | 588,569 | | Power Generation | 5,673 | | 807 | | | 47,931 | | 100 | | | 54,511 | | Mining | 13,689 | | 483 | | | 14,248 | | 681 | | | 29,101 | | Inter-company eliminations | — | | — | | | (77,551) | | (967) | | | (78,518) | | Total | $ | 998,640 | | $ | 7,364 | | | $ | — | | $ | — | | | $ | 1,006,004 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Six Months Ended June 30, 2020 | External Operating Revenue | | Inter-company Operating Revenue | | Total Revenues | Contract Customers | Other Revenues | Contract Customers | Other Revenues | Segment: | | | | | | | | Electric Utilities | $ | 323,700 | | $ | 1,850 | | | $ | 11,789 | | $ | — | | | $ | 337,339 | | Gas Utilities | 514,111 | | 6,220 | | | 1,552 | | — | | | 521,883 | | Power Generation | 3,097 | | 792 | | | 48,088 | | 111 | | | 52,088 | | Mining | 13,494 | | 700 | | | 15,755 | | 672 | | | 30,621 | | Inter-company eliminations | — | | — | | | (77,184) | | (783) | | | (77,967) | | Total | $ | 854,402 | | $ | 9,562 | | | $ | — | | $ | — | | | $ | 863,964 | |
| | | | | | | | | | | | | | | | | | | | | Three Months Ended June 30, | Six Months Ended June 30, | | 2021 | 2020 | 2021 | 2020 | Adjusted operating income: | | | | | Electric Utilities | $ | 35,568 | | $ | 33,993 | | $ | 57,381 | | $ | 69,643 | | Gas Utilities | 19,985 | | 18,209 | | 122,079 | | 121,106 | | Power Generation | 8,250 | | 11,402 | | 22,519 | | 22,751 | | Mining | 3,644 | | 3,358 | | 6,905 | | 6,487 | | Corporate and Other | (181) | | (29) | | (3,303) | | 131 | | Operating income | 67,266 | | 66,933 | | 205,581 | | 220,118 | | | | | | | Interest expense, net | (38,202) | | (35,545) | | (75,802) | | (70,998) | | Impairment of investment | — | | — | | — | | (6,859) | | Other income (expense), net | (191) | | (1,863) | | 75 | | 490 | | Income tax (expense) | (586) | | (4,831) | | (1,080) | | (20,833) | | Net income | 28,287 | | 24,694 | | 128,774 | | 121,918 | | Net income attributable to noncontrolling interest | (3,126) | | (3,728) | | (7,297) | | (7,778) | | Net income available for common stock | $ | 25,161 | | $ | 20,966 | | $ | 121,477 | | $ | 114,140 | |
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