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Long-Term Debt- Additional Information (Details) - First Mortgage [Member] $ in Millions | Dec. 31, 2021 USD ($)
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Debt Instrument [Line Items] |
Debt Instrument, Interest Rate, Stated Percentage | 8.00%
Avista Utilities [Member] |
Debt Instrument [Line Items] |
Amount of First Mortgage Bonds that Could be Issued, Percent | 66.66%
Amount of First Mortgage Bonds that Could be Issued | $ 1,800.0
Alaska Electric Light & Power [Member] |
Debt Instrument [Line Items] |
Amount of First Mortgage Bonds that Could be Issued, Percent | 66.66%
Amount of First Mortgage Bonds that Could be Issued | $ 38.2

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- Definition Amount Of First Mortgage Bonds That Could Be Issued + References No definition available. + Details
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- Definition Amount of First Mortgage Bonds that Could be Issued, Percent + References No definition available. + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Details
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- Details
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Period Type: |

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- Details
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