v2.3.0.11

Debt (Details 3) (USD $)
In Millions

Jun. 30, 2011

Dec. 31, 2010

Fair value

Fair and carrying values of debt instruments [Line Items]

First Lien Notes

$ 6,032

^[1]

$ 4,695

^[1]

Project financing, notes payable and other

1,355

^[2],[3],[4]

1,673

^[2],[3],[4]

Term Loan

1,638

^[1],[3]

^[1],[3]

NDH Project Debt

^[1]

1,303

^[1]

First Lien Credit Facility

^[1]

1,182

^[1]

CCFC Notes

1,073

1,067

Carrying value

Fair and carrying values of debt instruments [Line Items]

First Lien Notes

5,891

^[1]

4,691

^[1]

Project financing, notes payable and other

1,378

^[2],[3],[4]

1,708

^[2],[3],[4]

Term Loan

1,654

^[1],[3]

^[1],[3]

NDH Project Debt

^[1]

1,258

^[1]

First Lien Credit Facility

^[1]

1,184

^[1]

CCFC Notes

$ 969

$ 965

[1]	On March 9, 2011, we repaid and terminated the NDH Project Debt with proceeds received from the Term Loan, and on January 14, 2011, we repaid and terminated the First Lien Credit Facility with the issuance of the 2023 First Lien Notes as discussed above.
[2]	Excludes leases that are accounted for as failed sale-leaseback transactions under U.S. GAAP and included in our project financing, notes payable and other balance.
[3]	On June 17, 2011, we repaid approximately $340 million of project debt with the proceeds received from $360 million in borrowings under the New Term Loan as described above.
[4]	On June 24, 2011, we closed on the approximately $845 million Russell City Project Debt to fund the construction of Russell City as described above.

X

- Definition

Notes Payable, Other Payables, Disclosure

+ Details

Name:	cpn_NotesPayableOtherPayablesDisclosure
Namespace Prefix:	cpn
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Project Debt, Fair Value Disclosure

+ Details

Name:	cpn_ProjectDebtDisclosure
Namespace Prefix:	cpn
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Subsidiaries Notes Disclosure

+ Details

Name:	cpn_SubsidiariesNotesDisclosure
Namespace Prefix:	cpn
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of lines of credit at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

+ Details

Name:	us-gaap_LinesOfCreditFairValueDisclosure
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of Loans Payable at the balance sheet date.

+ Details

Name:	us-gaap_LoansPayableFairValueDisclosure
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents notes payable as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 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 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_NotesPayableFairValueDisclosure
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant