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v3.19.3.a.u2

Long-Term Debt (Narrative) (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 USD ($) Caontracts | Dec. 31, 2018 USD ($) | Dec. 31, 2017
Debt Instrument [Line Items] |  |  |
Secured Debt | $ 1,979,200 | $ 1,889,200 |
Debt Instrument, Interest Rate, Stated Percentage | 2.79% | 3.61% | 2.36%
Avista Utilities [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Secured Debt | $ 1,904,200 | $ 1,814,200 |
Avista Utilities [Member] | First Mortgage [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 | $ 1,500,000 |  |
Alaska Electric Light & Power [Member] | First Mortgage [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 | $ 30,400 |  |
2019 | Interest Rate Swap [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Settled Derivative Notional Amount | $ 70,000 |  |
Number of Interest Rate Swaps Settled | Caontracts | 6 |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: 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=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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