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The minimum amount of damages claimed by the plaintiff.

+ References

No definition available.

+ Details

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- Definition

The number of factors considered in the assessment of estimating an amount or range of reasonably possible loss by the entity.

+ References

No definition available.

+ Details

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- Definition

Amount of loss contingency liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Commitments and Contingencies, Legal Contingencies (Details) (USD $)	3 Months Ended								12 Months Ended			13 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2001
Legal Contingencies [Abstract]
Sales to the City of Seattle	$ 1,136,791,000us-gaap_Revenues	$ 1,049,111,000us-gaap_Revenues	$ 993,704,000us-gaap_Revenues	$ 1,203,543,000us-gaap_Revenues	$ 1,074,442,000us-gaap_Revenues	$ 1,044,300,000us-gaap_Revenues	$ 966,429,000us-gaap_Revenues	$ 1,117,457,000us-gaap_Revenues	$ 4,383,149,000us-gaap_Revenues	$ 4,202,628,000us-gaap_Revenues	$ 3,969,293,000us-gaap_Revenues
Pacific Northwest FERC Refund Proceeding [Member]
Legal Contingencies [Abstract]
Accrual for legal contingency	0								0
Minimum amount of damages claimed by plaintiff	34,000,000								34,000,000
Sales to the City of Seattle												50,000,000
Estimated City of Seattle's claim for refunds not including interest	$ 28,000,000								$ 28,000,000
Number of factors considered in assessment									2