[Line Items] for Accounting Policies [Table]

No definition available.

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- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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- Definition

The amount of a reclassification adjustment made to prior period financial statement amounts.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ 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 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

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- Definition

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

+ References

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Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Accounting Policies [Line Items]
Prior Period Reclassification Adjustment			$ 152
Current	$ 167		216
Non-current	17		12
Total	184		228
Interest costs capitalized	4	$ 5
Debt service
Accounting Policies [Line Items]
Current	29		28
Non-current	7		8
Total	36		36
Construction major maintenance
Accounting Policies [Line Items]
Current	45		50
Non-current	7		2
Total	52		52
Security project insurance
Accounting Policies [Line Items]
Current	91		136
Non-current	1		0
Total	92		136
Other
Accounting Policies [Line Items]
Current	2		2
Non-current	2		2
Total	$ 4		$ 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