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- Definition

Trade Receivables Sold

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Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Amount of interest capitalized during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements.

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- Definition

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that continue to be recognized in the statement of financial position. Includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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- Definition

Fair value of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction.

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Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Accounting Policies [Line Items]
Goodwill, Beginning Balance	$ 187
Goodwill, Ending Balance	233
Current	162		$ 173
Non-current	15		15
Total	177		188
Interest costs capitalized	7	$ 4
Transfer of Financial Assets Accounted for as Sales, Fair Value of Derecognized Assets	179		211
Continuing Involvement with Continued to be Recognized Transferred Financial Assets, Amount Outstanding	40		32
Trade Receivables Sold	542
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	546
Debt service
Accounting Policies [Line Items]
Current	12		11
Non-current	7		8
Total	19		19
Construction major maintenance
Accounting Policies [Line Items]
Current	48		45
Non-current	6		6
Total	54		51
Security project insurance
Accounting Policies [Line Items]
Current	99		114
Non-current	0		0
Total	99		114
Other
Accounting Policies [Line Items]
Current	3		3
Non-current	2		1
Total	$ 5		$ 4
Geothermal Properties, Gross [Member] \| Minimum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	13 years
Geothermal Properties, Gross [Member] \| Maximum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	58 years
Property, Plant and Equipment, Other Types [Member] \| Minimum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Property, Plant and Equipment, Other Types [Member] \| Maximum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	46 years
Building, Machinery and Equipment, Gross [Member] \| Minimum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Building, Machinery and Equipment, Gross [Member] \| Maximum [Member]
Accounting Policies [Line Items]
Property, plant and equipment, estimated useful lives	46 years
Texas [Member]
Accounting Policies [Line Items]
Goodwill, Beginning Balance	$ 31
Goodwill, Ending Balance	31
East [Member]
Accounting Policies [Line Items]
Goodwill, Beginning Balance	88
Goodwill, Ending Balance	135
West [Member]
Accounting Policies [Line Items]
Goodwill, Beginning Balance	68
Goodwill, Ending Balance	67
Calpine Solutions [Member]
Accounting Policies [Line Items]
Goodwill, Purchase Accounting Adjustments	(3)
Calpine Solutions [Member] \| Texas [Member]
Accounting Policies [Line Items]
Goodwill, Purchase Accounting Adjustments	0
Calpine Solutions [Member] \| East [Member]
Accounting Policies [Line Items]
Goodwill, Purchase Accounting Adjustments	(2)
Calpine Solutions [Member] \| West [Member]
Accounting Policies [Line Items]
Goodwill, Purchase Accounting Adjustments	(1)
North American Power [Member]
Accounting Policies [Line Items]
Goodwill, Acquired During Period	49
North American Power [Member] \| Texas [Member]
Accounting Policies [Line Items]
Goodwill, Acquired During Period	0
North American Power [Member] \| East [Member]
Accounting Policies [Line Items]
Goodwill, Acquired During Period	49
North American Power [Member] \| West [Member]
Accounting Policies [Line Items]
Goodwill, Acquired During Period	$ 0