v2.4.0.6

Debt (Project Financing, Notes Payable and Others) (Details) (USD $)
In Millions, unless otherwise specified

Dec. 31, 2012

Dec. 31, 2011

Debt Instrument [Line Items]

Long-term Debt

$ 10,750

$ 10,425

Steamboat [Member]

Debt Instrument [Line Items]

Long-term Debt

507

244

Debt Instrument, Interest Rate, Effective Percentage

3.60%

^[1]

4.10%

^[1]

OMEC [Member]

Debt Instrument [Line Items]

Long-term Debt

428

437

Debt Instrument, Interest Rate, Effective Percentage

6.80%

^[1]

6.60%

^[1]

Russell City Project [Member]

Debt Instrument [Line Items]

Long-term Debt

345

355

Debt Instrument, Interest Rate, Effective Percentage

6.80%

^[1]

6.80%

^[1]

BRSP [Member]

Debt Instrument [Line Items]

Long-term Debt

209

83

Debt Instrument, Interest Rate, Effective Percentage

3.50%

^[1]

3.80%

^[1]

Pasadena [Member]

Debt Instrument [Line Items]

Long-term Debt

160

^[2]

185

^[2]

Debt Instrument, Interest Rate, Effective Percentage

8.90%

^[1],[2]

8.80%

^[1],[2]

Bethpage [Member]

Debt Instrument [Line Items]

Long-term Debt

93

^[3]

98

^[3]

Debt Instrument, Interest Rate, Effective Percentage

7.00%

^[1],[3]

7.00%

^[1],[3]

Los Esteros Project [Member]

Debt Instrument [Line Items]

Long-term Debt

33

49

Debt Instrument, Interest Rate, Effective Percentage

10.80%

^[1]

10.60%

^[1]

Gilroy note payable [Member]

Debt Instrument [Line Items]

Long-term Debt

0

^[4]

232

^[4]

Debt Instrument, Interest Rate, Effective Percentage

0.00%

^[1],[4]

5.70%

^[1],[4]

Other Credit Derivatives [Member]

Debt Instrument [Line Items]

Long-term Debt

14

8

Debt Instrument, Interest Rate, Effective Percentage

0.00%

^[1]

0.00%

^[1]

Project Financing Total [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 1,789

$ 1,691

[1]	Our weighted average interest rate calculation includes the amortization of deferred financing costs and debt discount or premium.
[2]	Represents a sale-leaseback transaction that is accounted for as financing transaction under U.S. GAAP.
[3]	Represents a weighted average of first and second lien loans for the weighted average effective interest rates.
[4]	During the fourth quarter of 2012, we repaid the Calpine BRSP project debt with proceeds received from the issuance of our 2019 First Lien Term Loan.

X

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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X

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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