v3.8.0.1

Segment Information | 9 Months Ended
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Sep. 30, 2017
Segment Reporting [Abstract] |
Segment Information | Segment Information We assess our business on a regional basis due to the effect on our financial performance of the differing characteristics of these regions, particularly with respect to competition, regulation and other factors affecting supply and demand. At September 30, 2017, our reportable segments were West (including geothermal), Texas and East (including Canada). The results of our retail subsidiaries are reflected in the segment which corresponds with the geographic area in which the retail sales occur. We continue to evaluate the optimal manner in which we assess our performance including our segments and future changes may result in changes to the composition of our geographic segments. Commodity Margin is a key operational measure reviewed by our chief operating decision maker to assess the performance of our segments. The tables below show our financial data for our segments for the periods indicated (in millions):
| Three Months Ended September 30, 2017
| West |  | Texas |  | East |  | Consolidation and Elimination |  | Total
Revenues from external customers | $ | 553 |  |  | $ | 1,127 |  |  | $ | 906 |  |  | $ | — |  |  | $ | 2,586 |
Intersegment revenues | 2 |  |  | 4 |  |  | 2 |  |  | (8 | ) |  | — |
Total operating revenues | $ | 555 |  |  | $ | 1,131 |  |  | $ | 908 |  |  | $ | (8 | ) |  | $ | 2,586 |
Commodity Margin | $ | 327 |  |  | $ | 201 |  |  | $ | 336 |  |  | $ | — |  |  | $ | 864 |
Add: Mark-to-market commodity activity, net and other(1) | (40 | ) |  | 88 |  |  | (39 | ) |  | (8 | ) |  | 1 |
Less: |  |  |  |  |  |  |  |  |
Plant operating expense | 83 |  |  | 77 |  |  | 75 |  |  | (7 | ) |  | 228 |
Depreciation and amortization expense | 63 |  |  | 61 |  |  | 55 |  |  | — |  |  | 179 |
Sales, general and other administrative expense | 10 |  |  | 16 |  |  | 10 |  |  | 1 |  |  | 37 |
Other operating expenses | 13 |  |  | 6 |  |  | 6 |  |  | (2 | ) |  | 23 |
Impairment losses | — |  |  | 12 |  |  | — |  |  | — |  |  | 12 |
(Income) from unconsolidated subsidiaries | — |  |  | — |  |  | (7 | ) |  | — |  |  | (7 | )
Income from operations | 118 |  |  | 117 |  |  | 158 |  |  | — |  |  | 393 |
Interest expense |  |  |  |  |  |  |  |  | 156 |
Debt extinguishment costs and other (income) expense, net |  |  |  |  |  |  |  |  | 8 |
Income before income taxes |  |  |  |  |  |  |  |  | $ | 229 |
| Three Months Ended September 30, 2016
| West |  | Texas |  | East |  | Consolidation and Elimination |  | Total
Revenues from external customers | $ | 524 |  |  | $ | 1,067 |  |  | $ | 764 |  |  | $ | — |  |  | $ | 2,355 |
Intersegment revenues | 1 |  |  | 3 |  |  | 2 |  |  | (6 | ) |  | — |
Total operating revenues | $ | 525 |  |  | $ | 1,070 |  |  | $ | 766 |  |  | $ | (6 | ) |  | $ | 2,355 |
Commodity Margin | $ | 298 |  |  | $ | 198 |  |  | $ | 324 |  |  | $ | — |  |  | $ | 820 |
Add: Mark-to-market commodity activity, net and other(1) | 11 |  |  | 110 |  |  | (51 | ) |  | (7 | ) |  | 63 |
Less: |  |  |  |  |  |  |  |  |
Plant operating expense | 79 |  |  | 65 |  |  | 78 |  |  | (7 | ) |  | 215 |
Depreciation and amortization expense | 56 |  |  | 53 |  |  | 52 |  |  | — |  |  | 161 |
Sales, general and other administrative expense | 9 |  |  | 13 |  |  | 12 |  |  | (1 | ) |  | 33 |
Other operating expenses | 8 |  |  | 2 |  |  | 7 |  |  | 1 |  |  | 18 |
(Income) from unconsolidated subsidiaries | — |  |  | — |  |  | (6 | ) |  | — |  |  | (6 | )
Income from operations | 157 |  |  | 175 |  |  | 130 |  |  | — |  |  | 462 |
Interest expense |  |  |  |  |  |  |  |  | 158 |
Other (income) expense, net |  |  |  |  |  |  |  |  | 7 |
Income before income taxes |  |  |  |  |  |  |  |  | $ | 297 |
| Nine Months Ended September 30, 2017
| West |  | Texas |  | East |  | Consolidation and Elimination |  | Total
Revenues from external customers | $ | 1,666 |  |  | $ | 2,723 |  |  | $ | 2,562 |  |  | $ | — |  |  | $ | 6,951 |
Intersegment revenues | 4 |  |  | 12 |  |  | 6 |  |  | (22 | ) |  | — |
Total operating revenues | $ | 1,670 |  |  | $ | 2,735 |  |  | $ | 2,568 |  |  | $ | (22 | ) |  | $ | 6,951 |
Commodity Margin | $ | 792 |  |  | $ | 516 |  |  | $ | 761 |  |  | $ | — |  |  | $ | 2,069 |
Add: Mark-to-market commodity activity, net and other(2) | (1 | ) |  | 28 |  |  | (65 | ) |  | (22 | ) |  | (60 | )
Less: |  |  |  |  |  |  |  |  |  |
Plant operating expense | 291 |  |  | 282 |  |  | 260 |  |  | (21 | ) |  | 812 |
Depreciation and amortization expense | 189 |  |  | 187 |  |  | 166 |  |  | — |  |  | 542 |
Sales, general and other administrative expense | 31 |  |  | 54 |  |  | 31 |  |  | 1 |  |  | 117 |
Other operating expenses | 30 |  |  | 12 |  |  | 23 |  |  | (2 | ) |  | 63 |
Impairment losses | 28 |  |  | 13 |  |  | — |  |  | — |  |  | 41 |
(Gain) on sale of assets, net | — |  |  | — |  |  | (27 | ) |  | — |  |  | (27 | )
(Income) from unconsolidated subsidiaries | — |  |  | — |  |  | (17 | ) |  | — |  |  | (17 | )
Income (loss) from operations | 222 |  |  | (4 | ) |  | 260 |  |  | — |  |  | 478 |
Interest expense |  |  |  |  |  |  |  |  | 469 |
Debt extinguishment costs and other (income) expense, net |  |  |  |  |  |  |  |  | 42 |
Loss before income taxes |  |  |  |  |  |  |  |  | $ | (33 | )
| Nine Months Ended September 30, 2016
| West |  | Texas |  | East |  | Consolidation and Elimination |  | Total
Revenues from external customers | $ | 1,159 |  |  | $ | 2,129 |  |  | $ | 1,846 |  |  | $ | — |  |  | $ | 5,134 |
Intersegment revenues | 4 |  |  | 10 |  |  | 9 |  |  | (23 | ) |  | — |
Total operating revenues | $ | 1,163 |  |  | $ | 2,139 |  |  | $ | 1,855 |  |  | $ | (23 | ) |  | $ | 5,134 |
Commodity Margin | $ | 749 |  |  | $ | 511 |  |  | $ | 797 |  |  | $ | — |  |  | $ | 2,057 |
Add: Mark-to-market commodity activity, net and other(2) | (5 | ) |  | 7 |  |  | (44 | ) |  | (21 | ) |  | (63 | )
Less: |  |  |  |  |  |  |  |  |
Plant operating expense | 268 |  |  | 236 |  |  | 258 |  |  | (21 | ) |  | 741 |
Depreciation and amortization expense | 168 |  |  | 159 |  |  | 163 |  |  | — |  |  | 490 |
Sales, general and other administrative expense | 27 |  |  | 43 |  |  | 36 |  |  | — |  |  | 106 |
Other operating expenses | 23 |  |  | 6 |  |  | 27 |  |  | (1 | ) |  | 55 |
Impairment losses | 13 |  |  | — |  |  | — |  |  | — |  |  | 13 |
(Income) from unconsolidated subsidiaries | — |  |  | — |  |  | (16 | ) |  | — |  |  | (16 | )
Income from operations | 245 |  |  | 74 |  |  | 285 |  |  | 1 |  |  | 605 |
Interest expense |  |  |  |  |  |  |  |  | 472 |
Debt extinguishment costs and other (income) expense, net |  |  |  |  |  |  |  |  | 33 |
Income before income taxes |  |  |  |  |  |  |  |  | $ | 100 |
_________
(1) | Includes $33 million and $40 million of lease levelization and $39 million and $25 million of amortization expense for the three months ended September 30, 2017 and 2016, respectively.
(2) | Includes $(13) million and $(2) million of lease levelization and $143 million and $79 million of amortization expense for the nine months ended September 30, 2017 and 2016, respectively.

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- Definition The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -URI http://asc.fasb.org/topic&trid=2134510 + Details
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