v2.4.0.8

Use of Collateral (Details) (USD $) In Millions, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Use of Collateral [Abstract] |  |  |  |
Margin deposits | $ 177 | [1] | $ 261 | [1]
Natural gas and power prepayments | 24 |  | 28 |
Total margin deposits and natural gas and power prepayments with our counterparties | 201 | [2] | 289 | [2]
Letters of credit issued | 444 |  | 488 |
First priority liens under power and natural gas agreements | 12 |  | 31 |
First priority liens under interest rate swap agreements | 115 |  | 132 |
Total letters of credit and first priority liens with our counterparties | 571 |  | 651 |
Margin deposits held by us posted by our counterparties | 67 | [1],[3] | 5 | [1],[3]
Letters of credit posted with us by our counterparties | 140 |  | 2 |
Total margin deposits and letters of credit posted with us by our counterparties | 207 |  | 7 |
Use of Collateral (Textuals) [Abstract] |  |  |  |
Margin And Prepayment Amounts Included In Other Assets | 11 |  | 17 |
Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses | $ 190 |  | $ 272 |
[1] | Balances are subject to master netting arrangements and presented on a gross basis on our Consolidated Condensed Balance Sheets. We do not offset fair value amounts recognized for derivative instruments executed with the same counterparty under a master netting arrangement for financial statement presentation, and we do not offset amounts recognized for the right to reclaim, or the obligation to return, cash collateral with corresponding derivative instrument fair values. See Note 6 for further discussion of our derivative instruments subject to master netting arrangements.
[2] | At September 30, 2014 and December 31, 2013, $190 million and $272 million, respectively, were included in margin deposits and other prepaid expense and $11 million and $17 million, respectively, were included in other assets on our Consolidated Condensed Balance Sheets.
[3] | Included in other current liabilities on our Consolidated Condensed Balance Sheets.

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- Definition Derivative Collateral Obligation To Return Cash And Letters Of Credit Posted By Counterparties + References No definition available. + Details
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Balance Type: | credit
Period Type: | instant

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- Definition Derivative Collateral Right To Reclaim Cash And Natural Gas And Power Prepayments Total + References No definition available. + Details
Name: | cpn_DerivativeCollateralRightToReclaimCashAndNaturalGasAndPowerPrepaymentsTotal
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition First priority liens under interest rate swap agreements + References No definition available. + Details
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Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition First priority liens under power and natural gas agreements + References No definition available. + Details
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Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Letters of credit issued + References No definition available. + Details
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Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Letters of Credit Issued and First Priority Liens Under Power Natural Gas And Interest Rate Swap Agreements + References No definition available. + Details
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Balance Type: | debit
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- Definition Letters Of Credit Posted By Counterparties + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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- Definition Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Margin And Prepayment Amounts Included In Other Assets + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Natural gas and power prepayments + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Details
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- Definition The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8,17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition This element represents money paid in advance to protect the provider of a product or service, such as a lessor, against damage or nonpayment by the buyer or tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Security deposits held may be interest or noninterest bearing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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