v3.4.0.3

Segment Information (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2016 | Mar. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | $ 1,615 | $ 1,646
Commodity Margin |  | 580 | 535
Add: Mark-to-market commodity activity, net and other | [1] | (91) | 101
Plant operating expense |  | 255 | 260
Depreciation and amortization expense |  | 180 | 158
Sales, general and other administrative expense |  | 38 | 37
Other operating expenses |  | 20 | 20
(Income) loss from unconsolidated investments in power plants |  | (7) | (5)
Income from operations |  | 3 | 166
Interest expense, net of interest income |  | 156 | 153
Other (income) expense, net |  | 6 | 2
Debt Extinguishment Costs and Other (Income) Expense, Net |  |  | 21
Loss before income taxes |  | (159) | (8)
Lease levelization |  | (22) | (24)
Amortization of Intangible Assets |  | 27 | 4
West [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 426 | 517
Commodity Margin |  | 197 | 218
Add: Mark-to-market commodity activity, net and other | [1] | 46 | 119
Plant operating expense |  | 91 | 106
Depreciation and amortization expense |  | 69 | 67
Sales, general and other administrative expense |  | 10 | 10
Other operating expenses |  | 8 | 10
(Income) loss from unconsolidated investments in power plants |  | 0 | 0
Income from operations |  | 65 | 144
Texas [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 535 | 584
Commodity Margin |  | 153 | 149
Add: Mark-to-market commodity activity, net and other | [1] | (110) | 41
Plant operating expense |  | 86 | 89
Depreciation and amortization expense |  | 53 | 49
Sales, general and other administrative expense |  | 16 | 17
Other operating expenses |  | 2 | 2
(Income) loss from unconsolidated investments in power plants |  | 0 | 0
Income from operations |  | (114) | 33
East [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 662 | 552
Commodity Margin |  | 230 | 168
Add: Mark-to-market commodity activity, net and other | [1] | (21) | (52)
Plant operating expense |  | 84 | 72
Depreciation and amortization expense |  | 58 | 42
Sales, general and other administrative expense |  | 12 | 10
Other operating expenses |  | 10 | 8
(Income) loss from unconsolidated investments in power plants |  | (7) | (5)
Income from operations |  | 52 | (11)
Consolidation, Eliminations [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | (8) | (7)
Commodity Margin |  | 0 | 0
Add: Mark-to-market commodity activity, net and other | [1] | (6) | (7)
Plant operating expense |  | (6) | (7)
Depreciation and amortization expense |  | 0 | 0
Sales, general and other administrative expense |  | 0 | 0
Other operating expenses |  | 0 | 0
(Income) loss from unconsolidated investments in power plants |  | 0 | 0
Income from operations |  | 0 | 0
Operating Segments [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 1,615 | 1,646
Operating Segments [Member] | West [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 424 | 515
Operating Segments [Member] | Texas [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 532 | 581
Operating Segments [Member] | East [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 659 | 550
Operating Segments [Member] | Consolidation, Eliminations [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 0 | 0
Intersegment Eliminations [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 0 | 0
Intersegment Eliminations [Member] | West [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 2 | 2
Intersegment Eliminations [Member] | Texas [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 3 | 3
Intersegment Eliminations [Member] | East [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | 3 | 2
Intersegment Eliminations [Member] | Consolidation, Eliminations [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Operating revenues |  | $ (8) | $ (7)
[1] | Includes $(22) million and $(24) million of lease levelization and $27 million and $4 million of amortization expense for the three months ended March 31, 2016 and 2015, respectively.

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