v2.4.1.9

Income Taxes (Income Tax Expense (Benefit)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
U.S.	$ 942us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	$ (13)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	$ 194us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic
International	26us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	29us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	24us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign
Total	$ 968cpn_IncomeLossBeforeIncomeTaxesAndDiscontinuedOperationsWithNoncontrollingInterest	$ 16cpn_IncomeLossBeforeIncomeTaxesAndDiscontinuedOperationsWithNoncontrollingInterest	$ 218cpn_IncomeLossBeforeIncomeTaxesAndDiscontinuedOperationsWithNoncontrollingInterest

X

- Definition

Income (loss) before income taxes and discontinued operations with noncontrolling interest

+ References

No definition available.

+ Details

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Namespace Prefix:	cpn_
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X

- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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X

- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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