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v3.8.0.1

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating revenues: |  |  |  |
Operating revenues |  | $ 4,443,351 | $ 4,128,828 | $ 4,014,052
Operation and maintenance: |  |  |  |
Operation and maintenance: |  | 3,130,802 | 2,893,299 | 2,805,223
Purchased natural gas sold |  | 430,954 | 382,753 | 450,114
Depreciation, depletion and amortization |  | 207,486 | 216,318 | 211,747
Taxes, other than income |  | 166,673 | 151,826 | 140,955
Electric fuel and purchased power |  | 78,724 | 75,512 | 86,238
Total operating expenses |  | 4,014,639 | 3,719,708 | 3,694,277
Operating income |  | 428,712 | 409,120 | 319,775
Other income |  | 4,103 | 4,956 | 18,457
Interest expense |  | 82,788 | 87,848 | 91,179
Income before income taxes |  | 350,027 | 326,228 | 247,053
Income taxes |  | 65,041 | 93,132 | 70,664
Income from continuing operations |  | 284,986 | 233,096 | 176,389
Loss from discontinued operations, net of tax (Note 2) | [1] | (3,783) | (300,354) | (834,080)
Net income (loss) |  | 281,203 | (67,258) | (657,691)
Loss from discontinued operations attributable to noncontrolling interest (Note 2) |  | 0 | (131,691) | (35,256)
Loss on redemption of preferred stocks (Note 8) |  | 600 | 0 | 0
Dividends declared on preferred stocks |  | 171 | 685 | 685
Earnings (loss) on common stock |  | $ 280,432 | $ 63,748 | $ (623,120)
Earnings (loss) per common share - basic: |  |  |  |
Earnings before discontinued operations |  | $ 1.46 | $ 1.19 | $ 0.90
Discontinued operations attributable to the Company, net of tax |  | (0.02) | (0.86) | (4.10)
Earnings (loss) per common share - basic |  | 1.44 | 0.33 | (3.20)
Earnings (loss) per common share - diluted: |  |  |  |
Earnings before discontinued operations |  | 1.45 | 1.19 | 0.90
Discontinued operations attributable to the Company, net of tax |  | (0.02) | (0.86) | (4.10)
Earnings (loss) per common share - diluted |  | $ 1.43 | $ 0.33 | $ (3.20)
Weighted average common shares outstanding - basic |  | 195,304 | 195,299 | 194,928
Weighted average common shares outstanding - diluted |  | 195,687 | 195,618 | 194,986
Regulated operations [Member] |  |  |  |
Operating revenues: |  |  |  |
Operating revenues |  | $ 1,244,759 | $ 1,141,454 | $ 1,149,038
Operation and maintenance: |  |  |  |
Operation and maintenance: |  | 323,120 | 312,404 | 278,171
Nonregulated operations [Member] |  |  |  |
Operating revenues: |  |  |  |
Operating revenues |  | 3,198,592 | 2,987,374 | 2,865,014
Operation and maintenance: |  |  |  |
Operation and maintenance: |  | $ 2,807,682 | $ 2,580,895 | $ 2,527,052
[1] | Includes eliminations for the presentation of income tax adjustments between continuing and discontinued operations.

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