XML 83 R58.htm IDEA: XBRL DOCUMENT
v3.20.2

Income Taxes - Summary of Significant Factors Impact on Difference Between Effective Tax Rate and Federal Statutory Rate (Parenthetical) (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Regulatory liabilities |  |  | $ 49,629 |  | $ 49,629 |  | $ 51,715
Non-plant excess deferred turnaround, amount |  |  | (8,390) | $ (5,091) | (8,476) | $ (5,601) |
WUTC |  |  |  |  |  |  |
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Non-plant excess deferred turnaround, amount | $ 8,400 |  |  |  |  |  |
IPUC |  |  |  |  |  |  |
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Non-plant excess deferred turnaround, amount |  | $ 5,100 |  |  |  |  |
Income Tax Related |  |  |  |  |  |  |
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Regulatory liabilities |  |  | $ 13,335 |  | $ 13,335 |  | $ 23,803
Income Tax Related | WUTC |  |  |  |  |  |  |
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Regulatory liabilities | $ 10,900 |  |  |  |  |  |
Income Tax Related | IPUC |  |  |  |  |  |  |
Effective Tax Rate Reconciliation [Line Items] |  |  |  |  |  |  |
Regulatory liabilities |  | $ 6,400 |  |  |  |  |

X
- Definition Effective Income Tax Rate Reconciliation, Excess Deferred Income Tax Reversal, Amount. + References No definition available. + Details
Name: | ava_EffectiveIncomeTaxRateReconciliationExcessDeferredIncomeTaxReversalAmount
Namespace Prefix: | ava_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Effective tax rate reconciliation. + References No definition available. + Details
Name: | ava_EffectiveTaxRateReconciliationLineItems
Namespace Prefix: | ava_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities 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 405 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
Name: | us-gaap_RegulatoryLiabilityCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=ava_WashingtonUtilitiesAndTransportationCommissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=ava_IdahoPublicUtilitiesCommissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=us-gaap_DeferredIncomeTaxChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |