Disposal Group Including Discontinued Operation Consideration Held in Escrow

No definition available.

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- Definition

Disposal Group Including Discontinued Operation Gross Consideration

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+ Details

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- Definition

Disposal Group Including Discontinued Operation Percentage of Gross Consideration Held in Escrow

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Name:	ava_DisposalGroupIncludingDiscontinuedOperationPercentageofGrossConsiderationHeldinEscrow
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- Definition

Disposal Group Not Discontinued Operation Gain (Loss) On Disposal Net of Tax

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No definition available.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
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- 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.

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No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

Assets Held for Sale Assets Held for Sale (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2019	Apr. 18, 2019	Mar. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent			89.20%
Subsequent Event [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group Including Discontinued Operation Gross Consideration		$ 17.5
Disposal Group Including Discontinued Operation Consideration Held in Escrow		$ 1.2
Disposal Group Including Discontinued Operation Percentage of Gross Consideration Held in Escrow		7.00%
Disposal Group, Including Discontinued Operation, Consideration		$ 16.6
Disposal Group Not Discontinued Operation Gain (Loss) On Disposal Net of Tax	$ 2.4