v3.3.0.814

Use of Collateral (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Use of Collateral [Abstract] |  |  |
Margin deposits | [1] | $ 167 | $ 96
Natural gas and power prepayments |  | 23 | 22
Total margin deposits and natural gas and power prepayments with our counterparties | [2] | 190 | 118
Letters of credit issued |  | 460 | 450
First priority liens under power and natural gas agreements |  | 28 | 48
First priority liens under interest rate swap agreements |  | 112 | 116
Total letters of credit and first priority liens with our counterparties |  | 600 | 614
Margin deposits held by us posted by our counterparties | [1],[3] | 15 | 47
Letters of credit posted with us by our counterparties |  | 125 | 61
Total margin deposits and letters of credit posted with us by our counterparties |  | 140 | 108
Use of Collateral (Textuals) [Abstract] |  |  |
Margin And Prepayment Amounts Included In Other Assets |  | 14 | 9
Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses |  | $ 176 | $ 109
[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, 2015 and December 31, 2014, $176 million and $109 million, respectively, were included in margin deposits and other prepaid expense and $14 million and $9 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.

X
- Definition Derivative Collateral Obligation To Return Cash And Letters Of Credit Posted By Counterparties + References No definition available. + Details
Name: | cpn_DerivativeCollateralObligationToReturnCashAndLettersOfCreditPostedByCounterparties
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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
Period Type: | instant

X
- Definition First priority liens under interest rate swap agreements + References No definition available. + Details
Name: | cpn_FirstPriorityLiensUnderInterestRateSwapAgreements
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

X
- Definition Letters of Credit Issued and First Priority Liens Under Power Natural Gas And Interest Rate Swap Agreements + References No definition available. + Details
Name: | cpn_LettersOfCreditIssuedAndFirstPriorityLiensUnderPowerNaturalGasAndInterestRateSwapAgreements
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Letters Of Credit Posted By Counterparties + References No definition available. + Details
Name: | cpn_LettersOfCreditPostedByCounterparties
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses + References No definition available. + Details
Name: | cpn_MarginAndPrepaymentAmountsIncludedInMarginDepositsAndOtherPrepaidExpenses
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Margin And Prepayment Amounts Included In Other Assets + References No definition available. + Details
Name: | cpn_MarginAndPrepaymentAmountsIncludedInOtherAssets
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Natural gas and power prepayments + References No definition available. + Details
Name: | cpn_NaturalGasAndPowerPrepayments
Namespace Prefix: | cpn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Use of Collateral Abstract + References No definition available. + Details
Name: | cpn_UseOfCollateralAbstract
Namespace Prefix: | cpn_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Use of Collateral Textuals Abstract + References No definition available. + Details
Name: | cpn_UseOfCollateralTextualsAbstract
Namespace Prefix: | cpn_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_MarginDepositAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | us-gaap_SecurityDepositLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant