XML 90 R72.htm IDEA: XBRL DOCUMENT
v3.19.1

Fair Value (Carrying Value And Estimated Fair Value Of Financial Instruments) (Details) $ in Thousands | Mar. 31, 2019 USD ($) $ / shares | Dec. 31, 2018 USD ($)
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Capital Lease Obligations |  | $ 57,210
Level 2 [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | $ 1,155,199 | 1,142,292
Level 2 [Member] | Reported Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | 1,053,500 | 1,053,500
Level 3 [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | 734,742 | 734,742
Level 3 [Member] | Reported Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | 767,000 | 767,000
Alaska Electric Light & Power [Member] | Capital Lease Obligations [Member] | Level 3 [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Capital Lease Obligations | 56,900 | 55,600
Alaska Electric Light & Power [Member] | Capital Lease Obligations [Member] | Level 3 [Member] | Reported Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Capital Lease Obligations | 56,545 | 57,210
Affiliated Entity [Member] | Level 3 [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | 38,145 | 38,145
Affiliated Entity [Member] | Level 3 [Member] | Reported Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Fair Value | $ 51,547 | $ 51,547
Measurement Input, Quoted Price [Member] | Secured and Unsecured Debt [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Measurement Input | $ / shares | 100.0 |
Measurement Input, Quoted Price [Member] | Minimum [Member] | Secured and Unsecured Debt [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Measurement Input | $ / shares | 74.00 |
Measurement Input, Quoted Price [Member] | Maximum [Member] | Secured and Unsecured Debt [Member] | Estimate of Fair Value Measurement [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term Debt, Measurement Input | $ / shares | 121.59 |

X
- Definition 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. + 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 Reference 3: 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=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_CapitalLeaseObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
Name: | us-gaap_LongTermDebtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Value of input used to measure long-term debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
Name: | us-gaap_LongTermDebtMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=ava_AlaskaElectricLightPowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_CapitalLeaseObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputQuotedPriceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=ava_SecuredandUnsecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |