v3.7.0.1

Commitments and Contingencies Commitments and Contingencies (Details) | 6 Months Ended
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Jun. 30, 2017
Other Commitments [Line Items] |
Outstanding claims related to guarantees | 0

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- Definition Outstanding claims related to guarantees + References No definition available. + Details
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Namespace Prefix: | cpn_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_OtherCommitmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration