v3.7.0.1

Segment Information (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | $ 2,084 |  | $ 1,164 |  | $ 4,365 |  | $ 2,779 |
Commodity Margin | 647 |  | 657 |  | 1,205 |  | 1,237 |
Add: Mark-to-market commodity activity, net and other | (92) | [1] | (35) | [1] | (61) | [2] | (126) | [2]
Plant operating expense | 302 |  | 271 |  | 584 |  | 526 |
Depreciation and amortization expense | 186 |  | 162 |  | 392 |  | 342 |
Sales, general and other administrative expense | 40 |  | 35 |  | 80 |  | 73 |
Other operating expenses | 20 |  | 17 |  | 40 |  | 37 |
Gain on sale of assets, net | 0 |  | 0 |  | (27) |  | 0 |
(Income) loss from unconsolidated investments in power plants | (6) |  | (3) |  | (10) |  | (10) |
Income from operations | 13 |  | 140 |  | 85 |  | 143 |
Interest expense, net of interest income | 154 |  | 157 |  | 313 |  | 314 |
Debt Extinguishment Costs and Other (Income) Expense, Net | 8 |  | 21 |  | 34 |  | 26 |
Loss before income taxes | (149) |  | (38) |  | (262) |  | (197) |
Lease levelization | (24) |  | (20) |  | (46) |  | (42) |
West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 401 |  | 212 |  | 1,115 |  | 638 |
Commodity Margin | 244 |  | 254 |  | 465 |  | 451 |
Add: Mark-to-market commodity activity, net and other | (38) | [1] | (62) | [1] | 39 | [2] | (16) | [2]
Plant operating expense | 111 |  | 98 |  | 208 |  | 189 |
Depreciation and amortization expense | 63 |  | 56 |  | 154 |  | 125 |
Sales, general and other administrative expense | 8 |  | 8 |  | 21 |  | 18 |
Other operating expenses | 8 |  | 7 |  | 17 |  | 15 |
Gain on sale of assets, net |  |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | 16 |  | 23 |  | 104 |  | 88 |
Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 802 |  | 534 |  | 1,604 |  | 1,069 |
Commodity Margin | 167 |  | 160 |  | 315 |  | 313 |
Add: Mark-to-market commodity activity, net and other | (30) | [1] | 7 | [1] | (60) | [2] | (103) | [2]
Plant operating expense | 109 |  | 85 |  | 205 |  | 171 |
Depreciation and amortization expense | 65 |  | 53 |  | 127 |  | 106 |
Sales, general and other administrative expense | 21 |  | 14 |  | 38 |  | 30 |
Other operating expenses | 3 |  | 2 |  | 6 |  | 4 |
Gain on sale of assets, net |  |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | (61) |  | 13 |  | (121) |  | (101) |
East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 888 |  | 427 |  | 1,660 |  | 1,089 |
Commodity Margin | 236 |  | 243 |  | 425 |  | 473 |
Add: Mark-to-market commodity activity, net and other | (18) | [1] | 28 | [1] | (26) | [2] | 7 | [2]
Plant operating expense | 89 |  | 96 |  | 185 |  | 180 |
Depreciation and amortization expense | 58 |  | 53 |  | 111 |  | 111 |
Sales, general and other administrative expense | 11 |  | 12 |  | 21 |  | 24 |
Other operating expenses | 8 |  | 10 |  | 17 |  | 20 |
Gain on sale of assets, net |  |  |  |  | (27) |  |  |
(Income) loss from unconsolidated investments in power plants | (6) |  | (3) |  | (10) |  | (10) |
Income from operations | 58 |  | 103 |  | 102 |  | 155 |
Consolidation, Eliminations [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | (7) |  | (9) |  | (14) |  | (17) |
Commodity Margin | 0 |  | 0 |  | 0 |  | 0 |
Add: Mark-to-market commodity activity, net and other | (6) | [1] | (8) | [1] | (14) | [2] | (14) | [2]
Plant operating expense | (7) |  | (8) |  | (14) |  | (14) |
Depreciation and amortization expense | 0 |  | 0 |  | 0 |  | 0 |
Sales, general and other administrative expense | 0 |  | 1 |  | 0 |  | 1 |
Other operating expenses | 1 |  | (2) |  | 0 |  | (2) |
Gain on sale of assets, net |  |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | 0 |  | 1 |  | 0 |  | 1 |
Operating Segments [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 2,084 |  | 1,164 |  | 4,365 |  | 2,779 |
Operating Segments [Member] | West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 401 |  | 211 |  | 1,113 |  | 635 |
Operating Segments [Member] | Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 797 |  | 530 |  | 1,596 |  | 1,062 |
Operating Segments [Member] | East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 886 |  | 423 |  | 1,656 |  | 1,082 |
Operating Segments [Member] | Consolidation, Eliminations [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 0 |  | 0 |  | 0 |  | 0 |
Intersegment Eliminations [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 0 |  | 0 |  | 0 |  | 0 |
Intersegment Eliminations [Member] | West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 0 |  | 1 |  | 2 |  | 3 |
Intersegment Eliminations [Member] | Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 5 |  | 4 |  | 8 |  | 7 |
Intersegment Eliminations [Member] | East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 2 |  | 4 |  | 4 |  | 7 |
Intersegment Eliminations [Member] | Consolidation, Eliminations [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | (7) |  | (9) |  | (14) |  | (17) |
Other Assets [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Amortization of Intangible Assets | $ 44 |  | $ 27 |  | $ 104 |  | $ 54 |
[1] | Includes $(24) million and $(20) million of lease levelization and $44 million and $27 million of amortization expense for the three months ended June 30, 2017 and 2016, respectively.
[2] | Includes $(46) million and $(42) million of lease levelization and $104 million and $54 million of amortization expense for the six months ended June 30, 2017 and 2016, respectively.

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