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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

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.

+ References

No definition available.

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Litigation (Details) $ in Millions	Mar. 28, 2017 USD ($)	Dec. 31, 2018 USD ($) unit	Dec. 31, 2017 USD ($)
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded to Other Party	$ 1.5
Colstrip Unit One and Two
Loss Contingencies [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Colstrip Unit Three and Four
Loss Contingencies [Line Items]
Equity Method Investment, Ownership Percentage		25.00%
Colstrip Unit One and Two
Loss Contingencies [Line Items]
Number of Units \| unit		2
Colstrip Regulatory Asset [Domain]
Loss Contingencies [Line Items]
Regulatory Assets		$ 130.7	$ 127.6