Long-Term Debt, Before Current Portion And Bonds Held by Company

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- Definition

Reclassification Adjustment from Long-Term Debt to Regulatory Assets

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Reclassification Adjustment from Long-Term Debt to Regulatory Liabilities

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- Definition

Settled Interest Rate Swaps

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No definition available.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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No definition available.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Amount, after accumulated amortization, of debt discount.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Noncurrent portion of a debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer.

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Carrying value at the balance sheet date of the noncurrent portion of a financial instrument used to receive debt funding on a regular basis with original maturities ranging from 5-10 years.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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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.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-Term Debt and Capital Leases Long-Term Debt and Capital Leases (Details) $ in Thousands		9 Months Ended
	Aug. 31, 2016 USD ($) Caontracts	Sep. 30, 2016 USD ($)	Dec. 31, 2015 USD ($) Caontracts
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.72%	1.29%
Long-term Pollution Control Bond, Noncurrent		$ (83,700)	$ (83,700)
Long-term Debt, Gross		1,536,700	1,626,700
Capital Lease Obligations		66,226	68,601
Settled Interest Rate Swaps		0	(26,515)
Debt Instrument, Unamortized Discount		(833)	(956)
Unamortized Debt Issuance Expense		(9,879)	(10,852)
Long-Term Debt, Before Current Portion And Bonds Held by Company		1,765,214	1,656,978
Long-term Debt and Capital Lease Obligations, Current		(3,257)	(93,167)
Long-term Debt and Capital Lease Obligations		$ 1,678,257	$ 1,480,111
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.29%	1.11%
Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.72%	1.29%
Unsecured Debt [Member] \| 2016 [Member]
Debt Instrument [Line Items]
Unsecured Debt			$ 0
Alaska Energy Resources Company [Member] \| Unsecured Debt [Member] \| 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2019
Debt Instrument, Interest Rate, Stated Percentage		3.85%
Unsecured Debt		$ 15,000	15,000
Avista Utilities [Member]
Debt Instrument [Line Items]
Secured Debt		1,446,700	1,536,700
Line of Credit, Noncurrent		$ 103,000	0
Avista Utilities [Member] \| First Mortgage [Member] \| 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2016
Debt Instrument, Interest Rate, Stated Percentage		0.84%
Secured Debt		$ 0	90,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2018 5.95% [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2018
Debt Instrument, Interest Rate, Stated Percentage		5.95%
Secured Debt		$ 250,000	250,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2019
Debt Instrument, Interest Rate, Stated Percentage		5.45%
Secured Debt		$ 90,000	90,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2020
Debt Instrument, Interest Rate, Stated Percentage		3.89%
Secured Debt		$ 52,000	52,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2022
Debt Instrument, Interest Rate, Stated Percentage		5.13%
Secured Debt		$ 250,000	250,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2035 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2035
Debt Instrument, Interest Rate, Stated Percentage		6.25%
Secured Debt		$ 150,000	150,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2037
Debt Instrument, Interest Rate, Stated Percentage		5.70%
Secured Debt		$ 150,000	150,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2040
Debt Instrument, Interest Rate, Stated Percentage		5.55%
Secured Debt		$ 35,000	35,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2041 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2041
Debt Instrument, Interest Rate, Stated Percentage		4.45%
Secured Debt		$ 85,000	85,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2044 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2044
Debt Instrument, Interest Rate, Stated Percentage		4.11%
Secured Debt		$ 60,000	60,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2045
Debt Instrument, Interest Rate, Stated Percentage		4.37%
Secured Debt		$ 100,000	100,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2047
Debt Instrument, Interest Rate, Stated Percentage		4.23%
Secured Debt		$ 80,000	80,000
Avista Utilities [Member] \| First Mortgage [Member] \| 2051 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description	12/1/2051
Debt Instrument, Interest Rate, Stated Percentage	3.54%
Secured Debt	$ 175,000
Avista Utilities [Member] \| Secured Debt [Member] \| 2018 7.39% to 7.45%[Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2018
Medium-term Notes, Noncurrent		$ 22,500	22,500
Avista Utilities [Member] \| Secured Debt [Member] \| 2018 7.39% to 7.45%[Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.39%
Avista Utilities [Member] \| Secured Debt [Member] \| 2018 7.39% to 7.45%[Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.45%
Avista Utilities [Member] \| Secured Debt [Member] \| 2023 7.18% to 7.54% [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2023
Medium-term Notes, Noncurrent		$ 13,500	13,500
Avista Utilities [Member] \| Secured Debt [Member] \| 2023 7.18% to 7.54% [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.18%
Avista Utilities [Member] \| Secured Debt [Member] \| 2023 7.18% to 7.54% [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.54%
Avista Utilities [Member] \| Secured Debt [Member] \| 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2028
Debt Instrument, Interest Rate, Stated Percentage		6.37%
Medium-term Notes, Noncurrent		$ 25,000	25,000
Avista Utilities [Member] \| Secured Debt [Member] \| 2032 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2032
Long-term Pollution Control Bond, Noncurrent		$ 66,700	66,700
Avista Utilities [Member] \| Secured Debt [Member] \| 2034 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2034
Long-term Pollution Control Bond, Noncurrent		$ 17,000	17,000
Avista Utilities [Member] \| Unsecured Debt [Member] \| 2016 [Member]
Debt Instrument [Line Items]
Unsecured Debt		$ 70,000
Alaska Electric Light & Power [Member] \| First Mortgage [Member] \| 2044 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date, Description		2044
Debt Instrument, Interest Rate, Stated Percentage		4.54%
Secured Debt		$ 75,000	$ 75,000
Interest Rate Swap [Member] \| 2016 [Member]
Debt Instrument [Line Items]
Number of Interest Rate Derivatives Held \| Caontracts	6		6
Derivative, Notional Amount	$ 115,000		$ 115,000
Regulatory Asset For Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Reclassification Adjustment from Long-Term Debt to Regulatory Assets		92,800	0
Regulatory Liability for Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Reclassification Adjustment from Long-Term Debt to Regulatory Liabilities		$ 12,800	$ 0