Asset Retirement Obligation Increase related to Boardman plant due to updated decommissioning study.

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- Definition

Interest in Pacific Northwest Intertie

+ References

No definition available.

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- Definition

The proportionate share of the reporting entity's interest (percent) in Boardman, a jointly owned utility plant.

+ References

No definition available.

+ Details

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- Definition

Jointly Owned Utility Plant, Proportionate Ownership Share of Boardman transferred

+ References

No definition available.

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment, acquired at the acquisition date.

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- Definition

The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financial Liability
-URI http://asc.fasb.org/extlink&oid=6513127

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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-Publisher FASB
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-Section 50
-Paragraph 1
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- Definition

The amount of inventory recognized as of the acquisition date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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-Publisher FASB
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-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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- Definition

Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Jointly-owned Plant Jointly Owned Plant (Details) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 1985
Property, Plant and Equipment [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share of Boardman transferred		10.00%		10.00%	15.00%		15.00%
Disposal Group, Including Discontinued Operation, Consideration		$ 8,000,000		$ 8,000,000	$ 1
Property, Plant and Equipment, Additions		7,000,000		7,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		4,000,000		4,000,000
Asset Retirement Obligation, Liabilities Incurred	$ 4,000,000	7,000,000	$ 2,000,000	15,000,000	$ 4,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		6,000,000		6,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities		$ 4,000,000		4,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities	$ 2,000,000		$ 2,000,000
Asset Retirement Obligation Increase related to Boardman plant				$ 7,000,000
Interest in Pacific Northwest Intertie							10.714%
Jointly Owned Utility Plant, Proportionate Ownership Share of Boardman	90.00%		90.00%		80.00%	65.00%