CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 82,952	$ 74,662
Accounts and notes receivable-less allowances of $44,354 and $43,958	141,659	203,452
Utility energy commodity derivative assets	1,678	1,139
Regulatory asset for utility derivatives	41,251	69,685
Investments and funds held for clients	114,226	118,536
Materials and supplies, fuel stock and natural gas stored	51,066	52,006
Deferred income taxes	35,792	30,473
Income taxes receivable	15,907	15,378
Other current assets	31,785	49,225
Total current assets	516,316	614,556
Net Utility Property:
Utility plant in service	3,994,743	3,887,384
Construction work in progress	116,624	79,322
Total	4,111,367	3,966,706
Less: Accumulated depreciation and amortization	1,170,845	1,105,930
Total net utility property	2,940,522	2,860,776
Other Non-current Assets:
Investment in exchange power-net	16,946	18,783
Investment in affiliated trusts	11,547	11,547
Goodwill	73,783	39,045
Long-term energy contract receivable of Spokane Energy	54,740	62,525
Other intangibles, property and investments-net	92,956	80,309
Total other non-current assets	249,972	212,209
Deferred Charges:
Regulatory assets for deferred income tax	76,616	84,576
Regulatory assets for pensions and other postretirement benefits	248,082	260,359
Other regulatory assets	102,998	119,738
Non-current utility energy commodity derivative assets	1,073	185
Non-current regulatory asset for utility derivatives	30,111	40,345
Other deferred charges	24,566	21,787
Total deferred charges	483,446	526,990
Total assets	4,190,256	4,214,531
Current Liabilities:
Accounts payable	140,536	166,954
Client fund obligations	113,614	118,325
Current portion of long-term debt	392	7,474
Current portion of nonrecourse long-term debt of Spokane Energy	14,631	13,668
Short-term borrowings	82,000	96,000
Utility energy commodity derivative liabilities	35,788	70,824
Natural gas deferrals	13,169	12,140
Other current liabilities	147,723	141,789
Total current liabilities	547,853	627,174
Long-term debt	1,148,047	1,169,826
Nonrecourse long-term debt of Spokane Energy	21,688	32,803
Long-term debt to affiliated trusts	51,547	51,547
Long-term borrowings under committed line of credit	58,000
Regulatory liability for utility plant retirement costs	231,497	227,282
Pensions and other postretirement benefits	214,838	246,177
Deferred income taxes	527,397	505,954
Other non-current liabilities and deferred credits	105,481	116,084
Total liabilities	2,906,348	2,976,847
Commitments and Contingencies (See Notes to Condensed Consolidated Financial Statements)
Redeemable Noncontrolling Interests	6,726	51,809
Avista Corporation Stockholders' Equity:
Common stock, no par value; 200,000,000 shares authorized; 59,754,870 and 58,422,781 shares outstanding	887,530	855,188
Accumulated other comprehensive loss	(4,897)	(5,637)
Retained earnings	377,111	336,150
Total Avista Corporation stockholders' equity	1,259,744	1,185,701
Noncontrolling Interests	17,438	174
Total equity	1,277,182	1,185,875
Total liabilities and equity	$ 4,190,256	$ 4,214,531