v3.5.0.2
Segment Information
 6 Months Ended
Jun. 30, 2016
Segment Reporting [Abstract]  
Segment Information
Segment Information
We assess our business on a regional basis due to the impact on our financial performance of the differing characteristics of these regions, particularly with respect to competition, regulation and other factors impacting supply and demand. At June 30, 2016, our reportable segments were West (including geothermal), Texas and East (including Canada). 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 June 30, 2016
 
West
 
Texas
 
East
 
Consolidation
and
Elimination
 
Total
Revenues from external customers
$
211

 
$
530

 
$
423

 
$
—

 
$
1,164

Intersegment revenues
1

 
4

 
4

 
(9
)
 
—

Total operating revenues
$
212

 
$
534

 
$
427

 
$
(9
)
 
$
1,164

Commodity Margin
$
254

 
$
160

 
$
243

 
$
—

 
$
657

Add: Mark-to-market commodity activity, net and other(1)
(62
)
 
7

 
28

 
(8
)
 
(35
)
Less:
 
 
 
 
 
 
 
 
 
Plant operating expense
98

 
85

 
96

 
(8
)
 
271

Depreciation and amortization expense
56

 
53

 
53

 
—

 
162

Sales, general and other administrative expense
8

 
14

 
12

 
1

 
35

Other operating expenses
7

 
2

 
10

 
(2
)
 
17

(Income) from unconsolidated investments in power plants
—

 
—

 
(3
)
 
—

 
(3
)
Income from operations
23

 
13

 
103

 
1

 
140

Interest expense, net of interest income
 
 
 
 
 
 
 
 
156

Debt extinguishment costs and other (income) expense, net
 
 
 
 
 
 
 
 
22

Loss before income taxes
 
 
 
 
 
 
 
 
$
(38
)

 
Three Months Ended June 30, 2015
 
West
 
Texas
 
East
 
Consolidation
and
Elimination
 
Total
Revenues from external customers
$
421

 
$
570

 
$
451

 
$
—

 
$
1,442

Intersegment revenues
—

 
5

 
2

 
(7
)
 
—

Total operating revenues
$
421

 
$
575

 
$
453

 
$
(7
)
 
$
1,442

Commodity Margin
$
240

 
$
170

 
$
247

 
$
—

 
$
657

Add: Mark-to-market commodity activity, net and other(1)
(14
)
 
10

 
30

 
(7
)
 
19

Less:
 
 
 
 
 
 
 
 
 
Plant operating expense
120

 
82

 
77

 
(7
)
 
272

Depreciation and amortization expense
65

 
50

 
45

 
—

 
160

Sales, general and other administrative expense
6

 
15

 
9

 
—

 
30

Other operating expenses
10

 
2

 
8

 
—

 
20

(Income) from unconsolidated investments in power plants
—

 
—

 
(7
)
 
—

 
(7
)
Income from operations
25

 
31

 
145

 
—

 
201

Interest expense, net of interest income
 
 
 
 
 
 
 
 
157

Debt modification costs and other (income) expense, net
 
 
 
 
 
 
 
 
18

Income before income taxes
 
 
 
 
 
 
 
 
$
26


 
Six Months Ended June 30, 2016
 
West
 
Texas
 
East
 
Consolidation
and
Elimination
 
Total
Revenues from external customers
$
635

 
$
1,062

 
$
1,082

 
$
—

 
$
2,779

Intersegment revenues
3

 
7

 
7

 
(17
)
 
—

Total operating revenues
$
638

 
$
1,069

 
$
1,089

 
$
(17
)
 
$
2,779

Commodity Margin
$
451

 
$
313

 
$
473

 
$
—

 
$
1,237

Add: Mark-to-market commodity activity, net and other(2)
(16
)
 
(103
)
 
7

 
(14
)
 
(126
)
Less:
 
 
 
 
 
 
 
 
 
Plant operating expense
189

 
171

 
180

 
(14
)
 
526

Depreciation and amortization expense
125

 
106

 
111

 
—

 
342

Sales, general and other administrative expense
18

 
30

 
24

 
1

 
73

Other operating expenses
15

 
4

 
20

 
(2
)
 
37

(Income) from unconsolidated investments in power plants
—

 
—

 
(10
)
 
—

 
(10
)
Income (loss) from operations
88

 
(101
)
 
155

 
1

 
143

Interest expense, net of interest income
 
 
 
 
 
 
 
 
312

Debt extinguishment costs and other (income) expense, net
 
 
 
 
 
 
 
 
28

Loss before income taxes
 
 
 
 
 
 
 
 
$
(197
)

 
Six Months Ended June 30, 2015
 
West
 
Texas
 
East
 
Consolidation
and
Elimination
 
Total
Revenues from external customers
$
936

 
$
1,151

 
$
1,001

 
$
—

 
$
3,088

Intersegment revenues
2

 
8

 
4

 
(14
)
 
—

Total operating revenues
$
938

 
$
1,159

 
$
1,005

 
$
(14
)
 
$
3,088

Commodity Margin
$
458

 
$
319

 
$
415

 
$
—

 
$
1,192

Add: Mark-to-market commodity activity, net and other(2)
105

 
51

 
(22
)
 
(14
)
 
120

Less:
 
 
 
 
 
 
 
 
 
Plant operating expense
226

 
171

 
149

 
(14
)
 
532

Depreciation and amortization expense
132

 
99

 
87

 
—

 
318

Sales, general and other administrative expense
16

 
32

 
19

 
—

 
67

Other operating expenses
20

 
4

 
16

 
—

 
40

(Income) from unconsolidated investments in power plants
—

 
—

 
(12
)
 
—

 
(12
)
Income from operations
169


64


134


—

 
367

Interest expense, net of interest income
 
 
 
 
 
 
 
 
310

Debt modification and extinguishment costs and other (income) expense, net
 
 
 
 
 
 
 
 
39

Income before income taxes
 
 
 
 
 
 
 
 
$
18

_________
(1)
Includes $(20) million and $(18) million of lease levelization and $27 million and $3 million of amortization expense for the three months ended June 30, 2016 and 2015, respectively.
(2)
Includes $(42) million and $(42) million of lease levelization and $54 million and $7 million of amortization expense for the six months ended June 30, 2016 and 2015, respectively.