v2.4.0.8

Segment Information (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | $ 2,187 |  | $ 2,050 |  | $ 6,091 |  | $ 4,863 |
Commodity Margin | 944 | [1] | 985 | [1] | 2,221 | [1] | 1,979 | [1]
Add: Mark-to-market commodity activity, net and other | (25) | [2] | 6 | [2] | 111 | [2] | 4 | [2]
Plant operating expense | 215 |  | 200 |  | 754 |  | 684 |
Depreciation and amortization expense | 153 |  | 150 |  | 453 |  | 441 |
Sales, general and other administrative expense | 37 |  | 33 |  | 108 |  | 102 |
Other operating expenses | 23 |  | 20 |  | 66 |  | 58 |
Impairment losses | 123 |  | 0 |  | 123 |  | 0 |
(Gain) on sale of assets, net | (753) |  | 0 |  | (753) |  | 0 |
(Income) loss from unconsolidated investments in power plants | (5) |  | (9) |  | (18) |  | (25) |
Income from operations | 1,126 |  | 597 |  | 1,599 |  | 723 |
Interest expense, net of interest income | 154 |  | 174 |  | 486 |  | 517 |
Debt extinguishment costs and other (income) expense, net | 344 |  | 7 |  | 361 |  | 83 |
Income before income taxes | 628 |  | 416 |  | 752 |  | 123 |
Commodity Margin for Six Southeast Power Plants Sold |  |  | 65 |  | 81 |  | 122 |
Lease levelization | 49 |  | 44 |  | (7) |  | 17 |
Contract amortization | 4 |  | 4 |  | 11 |  | 11 |
West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 715 |  | 621 |  | 1,696 |  | 1,484 |
Commodity Margin | 361 | [1] | 337 | [1] | 791 | [1] | 737 | [1]
Add: Mark-to-market commodity activity, net and other | 41 | [2] | 16 | [2] | 91 | [2] | (2) | [2]
Plant operating expense | 91 |  | 84 |  | 291 |  | 271 |
Depreciation and amortization expense | 65 |  | 58 |  | 183 |  | 164 |
Sales, general and other administrative expense | 11 |  | 9 |  | 28 |  | 24 |
Other operating expenses | 12 |  | 12 |  | 39 |  | 33 |
Impairment losses | 0 |  |  |  | 0 |  |  |
(Gain) on sale of assets, net | 0 |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | 223 |  | 190 |  | 341 |  | 243 |
Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 989 |  | 836 |  | 2,611 |  | 1,796 |
Commodity Margin | 346 | [1] | 328 | [1] | 644 | [1] | 537 | [1]
Add: Mark-to-market commodity activity, net and other | (64) | [2] | (5) | [2] | 74 | [2] | 18 | [2]
Plant operating expense | 77 |  | 56 |  | 250 |  | 214 |
Depreciation and amortization expense | 51 |  | 41 |  | 141 |  | 125 |
Sales, general and other administrative expense | 18 |  | 13 |  | 48 |  | 43 |
Other operating expenses | 1 |  | 2 |  | 4 |  | 4 |
Impairment losses | 0 |  |  |  | 0 |  |  |
(Gain) on sale of assets, net | 0 |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | 135 |  | 211 |  | 275 |  | 169 |
East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 490 |  | 631 |  | 1,853 |  | 1,662 |
Commodity Margin | 237 | [1] | 320 | [1] | 786 | [1] | 705 | [1]
Add: Mark-to-market commodity activity, net and other | 4 | [2] | 3 | [2] | (31) | [2] | 12 | [2]
Plant operating expense | 55 |  | 67 |  | 237 |  | 221 |
Depreciation and amortization expense | 38 |  | 51 |  | 129 |  | 153 |
Sales, general and other administrative expense | 8 |  | 10 |  | 32 |  | 34 |
Other operating expenses | 6 |  | 9 |  | 22 |  | 25 |
Impairment losses | 123 |  |  |  | 123 |  |  |
(Gain) on sale of assets, net | (753) |  |  |  | (753) |  |  |
(Income) loss from unconsolidated investments in power plants | (5) |  | (9) |  | (18) |  | (25) |
Income from operations | 769 |  | 195 |  | 983 |  | 309 |
Geography Consolidation and Elimination [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | (7) |  | (38) |  | (69) |  | (79) |
Commodity Margin | 0 | [1] | 0 | [1] | 0 | [1] | 0 | [1]
Add: Mark-to-market commodity activity, net and other | (6) | [2] | (8) | [2] | (23) | [2] | (24) | [2]
Plant operating expense | (8) |  | (7) |  | (24) |  | (22) |
Depreciation and amortization expense | (1) |  | 0 |  | 0 |  | (1) |
Sales, general and other administrative expense | 0 |  | 1 |  | 0 |  | 1 |
Other operating expenses | 4 |  | (3) |  | 1 |  | (4) |
Impairment losses | 0 |  |  |  | 0 |  |  |
(Gain) on sale of assets, net | 0 |  |  |  | 0 |  |  |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income from operations | (1) |  | 1 |  | 0 |  | 2 |
Operating Segments [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 2,187 |  | 2,050 |  | 6,091 |  | 4,863 |
Operating Segments [Member] | West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 714 |  | 620 |  | 1,692 |  | 1,482 |
Operating Segments [Member] | Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 985 |  | 842 |  | 2,592 |  | 1,820 |
Operating Segments [Member] | East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 488 |  | 588 |  | 1,807 |  | 1,561 |
Operating Segments [Member] | Geography Consolidation and Elimination [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 | 1 |  | 1 |  | 4 |  | 2 |
Intersegment Eliminations [Member] | Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 4 |  | (6) |  | 19 |  | (24) |
Intersegment Eliminations [Member] | East [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | 2 |  | 43 |  | 46 |  | 101 |
Intersegment Eliminations [Member] | Geography Consolidation and Elimination [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Operating revenues | $ (7) |  | $ (38) |  | $ (69) |  | $ (79) |
[1] | the three months ended September 30, 2014.
[2] | Includes $49 million and $44 million of lease levelization and $4 million and $4 million of amortization expense for the three months ended September 30, 2014 and 2013, respectively.

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