[Line Items] for Accounting Policies [Table]

No definition available.

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- Definition

The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

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

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

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Accounting Policies [Line Items]
Current	$ 162		$ 162		$ 195
Non-current	48		48		49
Total	210		210		244
Interest Costs Capitalized	4	$ 6	$ 9	$ 12
Treasury Stock, Shares, Acquired			22.1
Treasury Stock, Value, Acquired, Cost Method			$ 454
Treasury Stock Acquired, Average Cost Per Share			$ 20.50
Adjustments Related to Tax Withholding for Share-based Compensation			$ 11
Debt Service
Accounting Policies [Line Items]
Current	16		16		10
Non-current	25		25		25
Total	41		41		35
Rent Reserve
Accounting Policies [Line Items]
Current	0		0		4
Non-current	0		0		0
Total	0		0		4
Construction Major Maintenance
Accounting Policies [Line Items]
Current	50		50		54
Non-current	19		19		17
Total	69		69		71
Security Project Insurance
Accounting Policies [Line Items]
Current	93		93		127
Non-current	4		4		5
Total	97		97		132
Other
Accounting Policies [Line Items]
Current	3		3		0
Non-current	0		0		2
Total	$ 3		$ 3		$ 2
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			47 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			47 years