XML 40 R21.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Summary Of Significant Accounting Policies (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2017
Accounting Policies [Abstract] |
Schedule of Accumulated Other Comprehensive Income (Loss) | Accumulated Other Comprehensive Loss Accumulated other comprehensive loss, net of tax, consisted of the following as of March 31, 2017 and December 31, 2016 (dollars in thousands):
| March 31, |  | December 31,
| 2017 |  | 2016
Unfunded benefit obligation for pensions and other postretirement benefit plans - net of taxes of $3,977 and $4,075, respectively | $ | 7,385 |  |  | $ | 7,568 |
Reclassifications Out of Accumulated Other Comprehensive Loss by Component | The following table details the reclassifications out of accumulated other comprehensive loss by component for the three months ended March 31 (dollars in thousands).
|  | Amounts Reclassified from Accumulated Other Comprehensive Loss |  |
Details about Accumulated Other Comprehensive Loss Components |  | 2017 |  | 2016 |  | Affected Line Item in Statement of Income
Amortization of defined benefit pension items |  |  |  |
Amortization of net prior service cost |  | $ | (299 | ) |  | $ | (311 | ) |  | (a)
Amortization of net loss |  | 3,638 |  |  | 3,642 |  |  | (a)
Adjustment due to effects of regulation |  | (3,058 | ) |  | (5,223 | ) |  | (a) (b)
|  | 281 |  |  | (1,892 | ) |  | Total before tax
|  | (98 | ) |  | 663 |  |  | Tax benefit (expense)
|  | $ | 183 |  |  | $ | (1,229 | ) |  | Net of tax
(a) | These accumulated other comprehensive loss components are included in the computation of net periodic pension cost (see Note 4 for additional details).
Utility Taxes | Utility related taxes collected from customers (primarily state excise taxes and city utility taxes) are recorded as operating revenue and expense. Taxes other than income taxes consisted of the following items for the three months ended March 31 (dollars in thousands):
| 2017 |  | 2016
Utility related taxes | $ | 21,584 |  |  | $ | 18,365 |
Property taxes | 10,406 |  |  | 10,420 |
Other taxes | 672 |  |  | 600 |
Total | $ | 32,662 |  |  | $ | 29,385 |
Materials And Supplies Fuel Stock And Natural Gas Stored | Inventories of materials and supplies, fuel stock and stored natural gas are recorded at average cost for our regulated operations and the lower of cost or net realizable value for our non-regulated operations and consisted of the following as of March 31, 2017 and December 31, 2016 (dollars in thousands):
| March 31, |  | December 31,
| 2017 |  | 2016
Materials and supplies | $ | 42,198 |  |  | $ | 40,700 |
Fuel stock | 4,277 |  |  | 4,585 |
Stored natural gas | 709 |  |  | 8,029 |
Total | $ | 47,184 |  |  | $ | 53,314 |

X
- Definition Schedule Of Utilities Operating Revenue Expense Taxes [Table Text Block] + References No definition available. + Details
Name: | ava_ScheduleOfUtilitiesOperatingRevenueExpenseTaxesTableTextBlock
Namespace Prefix: | ava_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss). + References No definition available. + Details
Name: | us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
Name: | us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(c)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_ScheduleOfInventoryCurrentTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration