Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current Assets:
Cash and cash equivalents	$ 82,574	$ 75,464
Accounts and notes receivable-less allowances of $44,309 and $44,155, respectively	221,343	193,683
Utility energy commodity derivative assets	3,022	4,139
Regulatory asset for utility derivatives	10,829	35,082
Investments and funds held for clients	96,688	88,272
Materials and supplies, fuel stock and natural gas stored	44,946	47,455
Deferred income taxes	24,788	34,281
Income taxes receivable	7,783	2,777
Other current assets	57,706	24,641
Total current assets	549,679	505,794
Net Utility Property:
Utility plant in service	4,290,464	4,054,644
Construction work in progress	160,323	143,098
Total	4,450,787	4,197,742
Less: Accumulated depreciation and amortization	1,248,362	1,174,026
Total net utility property	3,202,425	3,023,716
Other Non-current Assets:
Investment in exchange power-net	13,883	16,333
Investment in affiliated trusts	11,547	11,547
Goodwill	76,257	75,959
Intangible assets-net of accumulated amortization of $36,634 and $26,030, respectively	39,576	46,256
Long-term energy contract receivable of Spokane Energy	40,619	52,033
Other property and investments-net	58,555	46,542
Total other non-current assets	240,437	248,670
Deferred Charges:
Regulatory assets for deferred income tax	71,421	79,406
Regulatory assets for pensions and other postretirement benefits	156,984	306,408
Other regulatory assets	102,915	103,946
Non-current utility energy commodity derivative assets	854	1,093
Non-current regulatory asset for utility derivatives	23,258	25,218
Other deferred charges	13,950	18,928
Total deferred charges	369,382	534,999
Total assets	4,361,923	4,313,179
Current Liabilities:
Accounts payable	182,088	198,914
Client fund obligations	99,117	87,839
Current portion of long-term debt	358	50,372
Current portion of nonrecourse long-term debt of Spokane Energy	16,407	14,965
Short-term borrowings	171,000	52,000
Utility energy commodity derivative liabilities	10,875	29,515
Other current liabilities	145,495	142,544
Total current liabilities	625,340	576,149
Long-term debt	1,272,425	1,178,367
Nonrecourse long-term debt of Spokane Energy	1,431	17,838
Long-term debt to affiliated trusts	51,547	51,547
Long-term borrowings under committed line of credit	46,000	54,000
Regulatory liability for utility plant retirement costs	242,850	234,128
Pensions and other postretirement benefits	122,513	283,985
Deferred income taxes	535,343	524,877
Other non-current liabilities and deferred credits	130,318	110,215
Total liabilities	3,027,767	3,031,106
Commitments and Contingencies (See Notes to Consolidated Financial Statements)
Redeemable Noncontrolling Interests	15,889	4,938
Avista Corporation Shareholders’ Equity:
Common stock, no par value; 200,000,000 shares authorized; 60,076,752 and 59,812,796 shares outstanding	896,993	889,237
Accumulated other comprehensive loss	(5,819)	(6,700)
Retained earnings	407,092	376,940
Total Avista Corporation shareholders’ equity	1,298,266	1,259,477
Noncontrolling Interests	20,001	17,658
Total equity	1,318,267	1,277,135
Total liabilities and equity	$ 4,361,923	$ 4,313,179