v2.3.0.11

Variable Interest Entities And Unconsolidated Investments (Details 1) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011		Dec. 31, 2010
Equity Method Investments Included on Balance Sheet [Abstract]
Equity amounts	$ 84		$ 80
Greenfield
Equity Method Investments Included on Balance Sheet [Abstract]
Ownership Interest	50.00%
Equity amounts	79	[1]	77
Whitby
Equity Method Investments Included on Balance Sheet [Abstract]
Ownership Interest	50.00%
Equity amounts	$ 5	[1]	$ 3
Russell City
Equity Method Investments Included on Balance Sheet [Abstract]
Ownership Interest	75.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Third Party Owners	25.00%
[1] Our risk of loss related to our unconsolidated VIEs is limited to our investment balance. While we also could be responsible for our pro rata portion of debt, holders of the debt of our unconsolidated investments do not have recourse to Calpine Corporation and its other subsidiaries. The debt of our unconsolidated investments is not reflected on our Consolidated Condensed Balance Sheets. At June 30, 2011, and December 31, 2010, equity method investee debt was approximately $514 million and $494 million, respectively, and based on our pro rata share of each of the investments, our share of such debt would be approximately $257 million and $247 million at June 30, 2011 and December 31, 2010, respectively.

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Equity Method Investments Included on Balance Sheet [Abstract]

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Minority Interest Ownership Percentage By Noncontrolling Third Party Owners

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph a (1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ 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 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6382870&loc=d3e33749-111570

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