Fair Value Inputs, Power Contract Costs

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- Definition

Fair Value Inputs, Price Per Megawatt-Hour

+ References

No definition available.

+ Details

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- Definition

Fair Value Inputs, Price Per Millions of BTU

+ References

No definition available.

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- Definition

Fair Value Measurements, Sensitivity Analysis, Hypothetical Increase or Decrease of Market Prices, Result on Fair Value

+ References

No definition available.

+ Details

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- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

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-Section 45

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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-Section 50

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-Publisher FASB

-Name FASB Staff Position (FSP)

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-Paragraph 10A, 10B

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 4, 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 15

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-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.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-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.

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- Definition

This element represents the sum of all intangible assets having statutory or estimated useful lives.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 33

-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.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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-Publisher FASB

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Fair Value Measurements Valuation Technicques for Measurement with Unobservable Inputs (Details) (USD $)		6 Months Ended					6 Months Ended								3 Months Ended
	Jun. 30, 2013	Jun. 30, 2013 Discounted cash flow [Member] Low [Member]	Jun. 30, 2013 Discounted cash flow [Member] High [Member]	Jun. 30, 2013 Discounted cash flow [Member] Weighted Average [Member]	Jun. 30, 2013 Commodity Contract [Member]	Dec. 31, 2012 Commodity Contract [Member]	Jun. 30, 2013 Electric portfolio [Member] Discounted cash flow [Member] Low [Member]	Jun. 30, 2013 Electric portfolio [Member] Discounted cash flow [Member] High [Member]	Jun. 30, 2013 Electric portfolio [Member] Discounted cash flow [Member] Weighted Average [Member]	Jun. 30, 2013 Natural gas portfolio [Member] Discounted cash flow [Member] Low [Member]	Jun. 30, 2013 Natural gas portfolio [Member] Discounted cash flow [Member] High [Member]	Jun. 30, 2013 Natural gas portfolio [Member] Discounted cash flow [Member] Weighted Average [Member]	Jun. 30, 2013 Level 3 [Member] Fair Value, Measurements, Recurring [Member] PUGET ENERGY [Member]	Dec. 31, 2012 Level 3 [Member] Fair Value, Measurements, Recurring [Member] PUGET ENERGY [Member]	Jun. 30, 2013 Priest Rapids Development [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Finite-Lived Intangible Assets, Net															$ 47,100,000
Derivative Assets					16,891,000	21,683,000
Derivative Liabilities													0	0
Price (per MWh)		30.85	65.35	48.47			13.09	44.76	32.46
Price (per MMBtu)										2.97	4.71	3.99
Fair Value Measurements, Sensitivity Analysis, Hypothetical Increase or Decrease of Market Prices, Result on Fair Value	24,100,000
Finite-lived Intangible Assets, Fair Value Disclosure	484,100,000														33,600,000
Impairment of Intangible Assets, Finite-lived															13,500,000
Fair Value Inputs, Power Contract Costs		$ 389,000	$ 6,845,000	$ 4,110,000