XML 45 R34.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Segment Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017 | Sep. 30, 2017
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Total operating revenues | $ 1,219,409 | $ 988,186 | $ 2,108,601 | $ 1,768,354 |
Purchased gas cost | 626,960 | 427,494 | 993,877 | 738,799 |
Operation and maintenance expense | 161,073 | 132,239 | 290,640 | 257,177 |
Depreciation and amortization expense | 89,381 | 77,667 | 177,755 | 154,625 |
Taxes, other than income, expense | 73,007 | 65,614 | 135,780 | 122,663 |
Operating income | 268,988 | 285,172 | 510,549 | 495,090 |
Miscellaneous income (expense) | (253) | 833 | (2,288) | (161) |
Interest charges | 27,304 | 26,944 | 58,813 | 57,974 |
Income (loss) from continuing operations before income taxes | 241,431 | 259,061 | 449,448 | 436,955 |
Income tax expense (benefit) | 62,439 | 97,049 | (43,676) | 160,905 |
Income from continuing operations | 178,992 | 162,012 | 493,124 | 276,050 |
Income from discontinued operations, net of tax |  |  | 0 | 10,994 |
Gain on sale of discontinued operations, net of tax | 0 | 2,716 | 0 | 2,716 |
Net income (loss) | 178,992 | 164,728 | 493,124 | 289,760 |
Capital expenditures | 310,740 | 261,423 | 693,978 | 559,385 |
Segment Reporting Information, Balance Sheet [Abstract] |  |  |  |  |
Net property, plant and equipment | 9,761,329 |  | 9,761,329 |  | $ 9,259,182
Total assets | 11,356,322 |  | 11,356,322 |  | 10,749,596
Reportable Subsegments [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 1,219,409 | 988,186 | 2,108,601 | 1,768,354 |
Intersubsegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 0 | 0 | 0 | 0 |
Distribution Segment [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Total operating revenues | 1,199,291 | 962,541 | 2,060,083 | 1,717,197 |
Purchased gas cost | 727,053 | 513,096 | 1,190,811 | 908,442 |
Operation and maintenance expense | 131,991 | 103,703 | 235,728 | 196,417 |
Depreciation and amortization expense | 65,649 | 61,302 | 131,083 | 122,459 |
Taxes, other than income, expense | 64,692 | 57,636 | 119,799 | 108,182 |
Operating income | 209,906 | 226,804 | 382,662 | 381,697 |
Miscellaneous income (expense) | 393 | 1,029 | (1,007) | 396 |
Interest charges | 16,898 | 16,925 | 38,266 | 38,043 |
Income (loss) from continuing operations before income taxes | 193,401 | 210,908 | 343,389 | 344,050 |
Income tax expense (benefit) | 48,158 | 79,763 | (50,953) | 127,541 |
Income from continuing operations |  | 131,145 |  | 216,509 |
Income from discontinued operations, net of tax |  |  |  | 0 |
Gain on sale of discontinued operations, net of tax |  | 0 |  | 0 |
Net income (loss) | 145,243 | 131,145 | 394,342 | 216,509 |
Capital expenditures | 224,235 | 208,185 | 465,484 | 430,669 |
Segment Reporting Information, Balance Sheet [Abstract] |  |  |  |  |
Net property, plant and equipment | 7,202,673 |  | 7,202,673 |  | 6,849,517
Total assets | 10,723,398 |  | 10,723,398 |  | 10,050,164
Distribution Segment [Member] | Reportable Subsegments [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 1,198,309 | 962,217 | 2,058,762 | 1,716,483 |
Distribution Segment [Member] | Intersubsegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 982 | 324 | 1,321 | 714 |
Pipeline and Storage Segment [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Total operating revenues | 120,955 | 111,972 | 247,418 | 221,924 |
Purchased gas cost | 433 | 725 | 1,345 | 1,080 |
Operation and maintenance expense | 29,393 | 28,536 | 55,533 | 60,804 |
Depreciation and amortization expense | 23,732 | 16,365 | 46,672 | 32,166 |
Taxes, other than income, expense | 8,315 | 7,978 | 15,981 | 14,481 |
Operating income | 59,082 | 58,368 | 127,887 | 113,393 |
Miscellaneous income (expense) | (646) | (196) | (1,281) | (557) |
Interest charges | 10,406 | 10,019 | 20,547 | 19,931 |
Income (loss) from continuing operations before income taxes | 48,030 | 48,153 | 106,059 | 92,905 |
Income tax expense (benefit) | 14,281 | 17,286 | 7,277 | 33,364 |
Income from continuing operations |  | 30,867 |  | 59,541 |
Income from discontinued operations, net of tax |  |  |  | 0 |
Gain on sale of discontinued operations, net of tax |  | 0 |  | 0 |
Net income (loss) | 33,749 | 30,867 | 98,782 | 59,541 |
Capital expenditures | 86,505 | 53,238 | 228,494 | 128,716 |
Segment Reporting Information, Balance Sheet [Abstract] |  |  |  |  |
Net property, plant and equipment | 2,558,656 |  | 2,558,656 |  | 2,409,665
Total assets | 2,779,330 |  | 2,779,330 |  | 2,621,601
Pipeline and Storage Segment [Member] | Reportable Subsegments [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 21,100 | 25,969 | 49,839 | 51,871 |
Pipeline and Storage Segment [Member] | Intersubsegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 99,855 | 86,003 | 197,579 | 170,053 |
Natural Gas Marketing Segment [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Total operating revenues |  | 0 |  | 0 |
Purchased gas cost |  | 0 |  | 0 |
Operation and maintenance expense |  | 0 |  | 0 |
Depreciation and amortization expense |  | 0 |  | 0 |
Taxes, other than income, expense |  | 0 |  | 0 |
Operating income |  | 0 |  | 0 |
Miscellaneous income (expense) |  | 0 |  | 0 |
Interest charges |  | 0 |  | 0 |
Income (loss) from continuing operations before income taxes |  | 0 |  | 0 |
Income tax expense (benefit) |  | 0 |  | 0 |
Income from continuing operations |  | 0 |  | 0 |
Income from discontinued operations, net of tax |  |  |  | 10,994 |
Gain on sale of discontinued operations, net of tax |  | 2,716 |  | 2,716 |
Net income (loss) |  | 2,716 |  | 13,710 |
Capital expenditures |  | 0 |  | 0 |
Natural Gas Marketing Segment [Member] | Reportable Subsegments [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues |  | 0 |  | 0 |
Natural Gas Marketing Segment [Member] | Intersubsegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues |  | 0 |  | 0 |
Intersegment Elimination [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Total operating revenues | (100,837) | (86,327) | (198,900) | (170,767) |
Purchased gas cost | (100,526) | (86,327) | (198,279) | (170,723) |
Operation and maintenance expense | (311) | 0 | (621) | (44) |
Depreciation and amortization expense | 0 | 0 | 0 | 0 |
Taxes, other than income, expense | 0 | 0 | 0 | 0 |
Operating income | 0 | 0 | 0 | 0 |
Miscellaneous income (expense) | 0 | 0 | 0 | 0 |
Interest charges | 0 | 0 | 0 | 0 |
Income (loss) from continuing operations before income taxes | 0 | 0 | 0 | 0 |
Income tax expense (benefit) | 0 | 0 | 0 | 0 |
Income from continuing operations |  | 0 |  | 0 |
Income from discontinued operations, net of tax |  |  |  | 0 |
Gain on sale of discontinued operations, net of tax |  | 0 |  | 0 |
Net income (loss) | 0 | 0 | 0 | 0 |
Capital expenditures | 0 | 0 | 0 | 0 |
Segment Reporting Information, Balance Sheet [Abstract] |  |  |  |  |
Net property, plant and equipment | 0 |  | 0 |  | 0
Total assets | (2,146,406) |  | (2,146,406) |  | $ (1,922,169)
Intersegment Elimination [Member] | Reportable Subsegments [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | 0 | 0 | 0 | 0 |
Intersegment Elimination [Member] | Intersubsegment Eliminations [Member] |  |  |  |  |
Segment Reporting Information Profit Loss [Abstract] |  |  |  |  |
Revenues | $ (100,837) | $ (86,327) | $ (198,900) | $ (170,767) |

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