Number of interest rate swaps settled

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- Definition

Payments for (proceeds from) derivative instrument operating activities

+ References

No definition available.

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- Definition

Settled derivative notional amount

+ References

No definition available.

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- Definition

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

+ References

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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- Definition

The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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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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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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Derivatives And Risk Management (Interest Rate Swap Agreements) (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) Caontracts	Dec. 31, 2018 USD ($) Caontracts	Dec. 31, 2017 USD ($) Caontracts
Derivatives, Fair Value [Line Items]
Secured Debt			$ 1,889,200	$ 1,786,700
Derivative, Fair Value, Amount Offset Against Collateral, Net			51,747	62,408
Payments for (proceeds from) derivative instrument operating activities		$ (26,600)
Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net			$ 530	$ 34,970
2018 \| Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of interest rate swaps settled \| Caontracts		14
Number of contracts \| Caontracts				14
Derivative, Notional Amount				$ 275,000
Derivative, Maturity Date				Dec. 31, 2018
Settled derivative notional amount	$ 275,000
2019 \| Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Caontracts			6	6
Derivative, Notional Amount			$ 70,000	$ 70,000
Derivative, Maturity Date			Dec. 31, 2019	Dec. 31, 2019
2020 \| Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Caontracts			6	3
Derivative, Notional Amount			$ 60,000	$ 30,000
Derivative, Maturity Date			Dec. 31, 2020	Dec. 31, 2020
2021 \| Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Caontracts			2	1
Derivative, Notional Amount			$ 25,000	$ 15,000
Derivative, Maturity Date			Dec. 31, 2021	Dec. 31, 2021
2022 \| Interest Rate Swap Agreements [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Caontracts			7	5
Derivative, Notional Amount			$ 80,000	$ 60,000
Derivative, Maturity Date			Dec. 31, 2022	Dec. 31, 2022
Avista Utilities [Member]
Derivatives, Fair Value [Line Items]
Secured Debt			$ 1,814,200	$ 1,711,700
First Mortgage [Member] \| 2048 4.35% \| Avista Utilities [Member]
Derivatives, Fair Value [Line Items]
Secured Debt			$ 375,000	$ 0