v2.4.0.8

Segment and Significant Customer Information (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | $ 1,572 |  | $ 879 |  | $ 2,813 |  | $ 2,115 |
Intersegment revenue | 0 |  | 0 |  | 0 |  | 0 |
Operating revenues | 1,572 |  | 879 |  | 2,813 |  | 2,115 |
Commodity Margin | 533 |  | 609 | [1],[2] | 994 |  | 1,126 | [1],[2]
Add: Mark-to-market commodity activity, net and other | 39 | [3] | (344) | [3] | (2) | [4] | (260) | [4]
Plant operating expense | 257 |  | 271 |  | 484 |  | 492 |
Depreciation and amortization expense | 145 |  | 138 |  | 291 |  | 278 |
Sales, general and other administrative expense | 36 |  | 35 |  | 69 |  | 68 |
Other operating expenses | 20 |  | 19 |  | 38 |  | 40 |
(Income) loss from unconsolidated investments in power plants | (8) |  | (5) |  | (16) |  | (14) |
Income (loss) from operations | 122 |  | (193) |  | 126 |  | 2 |
Interest expense, net of interest income | 169 |  | 182 |  | 343 |  | 364 |
Loss on interest rate derivatives | 0 |  | 0 |  | 0 |  | 14 |
Debt Extinguishment Costs and Other (Income) Expense, Net | 71 |  | 6 |  | 76 |  | 20 |
Income (loss) before income taxes | (118) |  | (381) |  | (293) |  | (396) |
Lease levelization | (11) |  | (1) |  | (27) |  | (9) |
Commodity Margin Riverside Energy Center |  |  | 24 |  |  |  | 32 |
Commodity Margin Broad River Energy Center |  |  | 13 |  |  |  | 24 |
Contract amortization | 3 |  | 3 |  | 7 |  | 7 |
West [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | 479 |  | 258 |  | 862 |  | 674 |
Intersegment revenue | 0 |  | 1 |  | 1 |  | 5 |
Operating revenues | 479 |  | 259 |  | 863 |  | 679 |
Commodity Margin | 198 |  | 210 | [1],[2] | 400 |  | 418 | [1],[2]
Add: Mark-to-market commodity activity, net and other | 19 | [3] | (76) | [3] | (18) | [4] | (40) | [4]
Plant operating expense | 88 |  | 112 |  | 181 |  | 193 |
Depreciation and amortization expense | 52 |  | 49 |  | 103 |  | 99 |
Sales, general and other administrative expense | 3 |  | 6 |  | 7 |  | 14 |
Other operating expenses | 11 |  | 9 |  | 20 |  | 20 |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income (loss) from operations | 63 |  | (42) |  | 71 |  | 52 |
Texas [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | 571 |  | 188 |  | 978 |  | 544 |
Intersegment revenue | (25) |  | 41 |  | (18) |  | 61 |
Operating revenues | 546 |  | 229 |  | 960 |  | 605 |
Commodity Margin | 133 |  | 145 | [1],[2] | 209 |  | 254 | [1],[2]
Add: Mark-to-market commodity activity, net and other | 34 | [3] | (217) | [3] | 23 | [4] | (183) | [4]
Plant operating expense | 96 |  | 72 |  | 164 |  | 140 |
Depreciation and amortization expense | 44 |  | 34 |  | 87 |  | 69 |
Sales, general and other administrative expense | 21 |  | 13 |  | 38 |  | 24 |
Other operating expenses | 1 |  | 1 |  | 2 |  | 3 |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income (loss) from operations | 5 |  | (192) |  | (59) |  | (165) |
North [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | 348 |  | 269 |  | 654 |  | 567 |
Intersegment revenue | 8 |  | 2 |  | 15 |  | 5 |
Operating revenues | 356 |  | 271 |  | 669 |  | 572 |
Commodity Margin | 159 |  | 181 | [1],[2] | 301 |  | 325 | [1],[2]
Add: Mark-to-market commodity activity, net and other | (12) | [3] | (3) | [3] | (5) | [4] | 9 | [4]
Plant operating expense | 46 |  | 58 |  | 90 |  | 103 |
Depreciation and amortization expense | 32 |  | 34 |  | 65 |  | 67 |
Sales, general and other administrative expense | 6 |  | 8 |  | 12 |  | 14 |
Other operating expenses | 7 |  | 6 |  | 14 |  | 15 |
(Income) loss from unconsolidated investments in power plants | (8) |  | (5) |  | (16) |  | (14) |
Income (loss) from operations | 64 |  | 77 |  | 131 |  | 149 |
Southeast [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | 174 |  | 164 |  | 319 |  | 330 |
Intersegment revenue | 71 |  | (6) |  | 104 |  | 16 |
Operating revenues | 245 |  | 158 |  | 423 |  | 346 |
Commodity Margin | 43 |  | 73 | [1],[2] | 84 |  | 129 | [1],[2]
Add: Mark-to-market commodity activity, net and other | 7 | [3] | (42) | [3] | 14 | [4] | (32) | [4]
Plant operating expense | 35 |  | 36 |  | 65 |  | 69 |
Depreciation and amortization expense | 18 |  | 22 |  | 37 |  | 45 |
Sales, general and other administrative expense | 7 |  | 7 |  | 12 |  | 15 |
Other operating expenses | (1) |  | 2 |  | 1 |  | 3 |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income (loss) from operations | (9) |  | (36) |  | (17) |  | (35) |
Consolidation and Elimination [Member] |  |  |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |  |  |
Revenue from External Customer | 0 |  | 0 |  | 0 |  | 0 |
Intersegment revenue | (54) |  | (38) |  | (102) |  | (87) |
Operating revenues | (54) |  | (38) |  | (102) |  | (87) |
Commodity Margin | 0 |  | 0 | [1],[2] | 0 |  | 0 | [1],[2]
Add: Mark-to-market commodity activity, net and other | (9) | [3] | (6) | [3] | (16) | [4] | (14) | [4]
Plant operating expense | (8) |  | (7) |  | (16) |  | (13) |
Depreciation and amortization expense | (1) |  | (1) |  | (1) |  | (2) |
Sales, general and other administrative expense | (1) |  | 1 |  | 0 |  | 1 |
Other operating expenses | 2 |  | 1 |  | 1 |  | (1) |
(Income) loss from unconsolidated investments in power plants | 0 |  | 0 |  | 0 |  | 0 |
Income (loss) from operations | $ (1) |  | $ 0 |  | $ 0 |  | $ 1 |
[1] | Our Southeast segment includes Commodity Margin of $13 million and $24 million for the three and six months ended June 30, 2012 related to Broad River, which was sold in December 2012.
[2] | Our North segment includes Commodity Margin of $24 million and $32 million for the three and six months ended June 30, 2012 related to Riverside Energy Center, LLC, which was sold in December 2012.
[3] | Includes $(11) million and $(1) million of lease levelization and $3 million and $3 million of amortization expense for the three months ended June 30, 2013 and 2012, respectively
[4] | Includes $(27) million and $(9) million of lease levelization and $7 million and $7 million of amortization expense for the six months ended June 30, 2013 and 2012, respectively.

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