v2.4.1.9

Debt Senior Unsecured Notes (Details) (USD $)

12 Months Ended

3 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2014

Feb. 03, 2015

Debt Instrument [Line Items]

Gains (Losses) on Extinguishment of Debt

$ (346,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt

$ (144,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt

$ (30,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt

Senior Unsecured Notes 2023 [Member]

Debt Instrument [Line Items]

Long-term Debt

1,250,000,000us-gaap_LongTermDebt
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= cpn_SeniorUnsecuredNotes2023Member

0us-gaap_LongTermDebt
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Debt Instrument, Interest Rate, Effective Percentage

5.60%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_LongtermDebtTypeAxis
= cpn_SeniorUnsecuredNotes2023Member

^[1]

0.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_LongtermDebtTypeAxis
= cpn_SeniorUnsecuredNotes2023Member

^[1]

Debt Instrument, Face Amount

1,250,000,000us-gaap_DebtInstrumentFaceAmount
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= cpn_SeniorUnsecuredNotes2023Member

Debt Instrument, Interest Rate, Stated Percentage

5.375%us-gaap_DebtInstrumentInterestRateStatedPercentage
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= cpn_SeniorUnsecuredNotes2023Member

Senior Unsecured Notes 2025 [Member]

Debt Instrument [Line Items]

Long-term Debt

1,550,000,000us-gaap_LongTermDebt
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= cpn_SeniorUnsecuredNotes2025Member

0us-gaap_LongTermDebt
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Debt Instrument, Interest Rate, Effective Percentage

5.90%us-gaap_DebtInstrumentInterestRateEffectivePercentage
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= cpn_SeniorUnsecuredNotes2025Member

^[1]

0.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_LongtermDebtTypeAxis
= cpn_SeniorUnsecuredNotes2025Member

^[1]

Debt Instrument, Face Amount

1,550,000,000us-gaap_DebtInstrumentFaceAmount
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= cpn_SeniorUnsecuredNotes2025Member

Debt Instrument, Interest Rate, Stated Percentage

5.75%us-gaap_DebtInstrumentInterestRateStatedPercentage
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= cpn_SeniorUnsecuredNotes2025Member

Unsecured Debt [Member]

Debt Instrument [Line Items]

Long-term Debt

2,800,000,000us-gaap_LongTermDebt
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= us-gaap_UnsecuredDebtMember

0us-gaap_LongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_UnsecuredDebtMember

2019, 2020 and 2021 First Lien Notes [Member]

Debt Instrument [Line Items]

Deferred Finance Costs, Net

42,000,000us-gaap_DeferredFinanceCostsNet
/ us-gaap_LongtermDebtTypeAxis
= cpn_A20192020and2021FirstLienNotesMember

Gains (Losses) on Extinguishment of Debt

(340,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_LongtermDebtTypeAxis
= cpn_A20192020and2021FirstLienNotesMember

First Lien Notes 2023 [Member]

Debt Instrument [Line Items]

Long-term Debt

840,000,000us-gaap_LongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= cpn_FirstLienNotes2023Member

^[2]

960,000,000us-gaap_LongTermDebt
/ us-gaap_LongtermDebtTypeAxis
= cpn_FirstLienNotes2023Member

^[2]

Debt Instrument, Interest Rate, Effective Percentage

8.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage
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= cpn_FirstLienNotes2023Member

^[1]

8.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage
/ us-gaap_LongtermDebtTypeAxis
= cpn_FirstLienNotes2023Member

^[1]

Subsequent Event [Member] | Senior Unsecured Notes 2024 [Member]

Debt Instrument [Line Items]

Debt Instrument, Face Amount

650,000,000us-gaap_DebtInstrumentFaceAmount
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= cpn_SeniorUnsecuredNotes2024Member
/ us-gaap_SubsequentEventTypeAxis
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Debt Instrument, Interest Rate, Stated Percentage

5.50%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= cpn_SeniorUnsecuredNotes2024Member
/ us-gaap_SubsequentEventTypeAxis
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Subsequent Event [Member] | First Lien Notes 2023 [Member] | Early Redemption Amount [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 150,000,000us-gaap_LongTermDebt
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= cpn_EarlyRedemptionAmountMember
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= cpn_FirstLienNotes2023Member
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[1]	Our weighted average interest rate calculation includes the amortization of deferred financing costs and debt discount.
[2]	In December 2014, we used cash on hand to redeem 10% of the original aggregate principal amount of our 2023 First Lien Notes, plus accrued and unpaid interest. On February 3, 2015, we additionally repurchased approximately $150 million of our 2023 First Lien Notes with the proceeds from our 2024 Senior Unsecured Notes, which is described in further detail below.

X

- Definition

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB

-Name Accounting Standards Codification

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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