XML 149 R108.htm IDEA: XBRL DOCUMENT v3.8.0.1

Common Stock Common Stock (Stock Repurchase Programs) (Details)	12 Months Ended
	Dec. 31, 2015 $ / shares
Schedule of Common Stock Repurchases [Line Items]
Treasury Stock Acquired, Average Cost Per Share	$ 32.66

X

- Definition

[Line Items] for Schedule of Common Stock Repurchases [Table]

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration