v2.4.0.8

Income Taxes (Schedule of Income Tax Expense (Benefit) Intraperiod Tax Allocation) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Continuing Operations [Member] |  |  |
Income Tax [Line Items] |  |  |
Deferred income tax liability, net of current | $ 1 | $ 9 | $ 42
Other Comprehensive Income (Loss) [Member] |  |  |
Income Tax [Line Items] |  |  |
Deferred income tax liability, net of current | $ (1) | $ (9) | $ (45)

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- Details
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Namespace Prefix: | cpn_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The sum of income tax expense or benefit for the period that has been allocated among continuing operations, discontinued operations, extraordinary items, other comprehensive income, and items charged or credited directly to shareholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=18498875&loc=d3e38679-109324 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration