Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Common Stock, Dividends, Per Share, Cash Paid	$ 0.3175	$ 0.305
Operating Revenues:
Utility revenues	$ 437,124	$ 431,127
Ecova revenues	44,384	42,407
Other non-utility revenues	9,454	9,372
Total operating revenues	490,962	482,906
Utility operating expenses:
Resource costs	220,497	229,630
Other operating expenses	67,337	65,444
Depreciation and amortization	30,726	27,935
Taxes other than income taxes	28,146	25,817
Ecova operating expenses:
Other operating expenses	37,877	35,990
Depreciation and Amortization	3,709	3,493
Other non-utility operating expenses:
Other operating expenses	9,383	9,345
Depreciation and amortization	147	190
Total operating expenses	397,822	397,844
Income from operations	93,140	85,062
Interest expense	19,084	19,692
Interest expense to affiliated trusts	111	118
Capitalized interest	(661)	(940)
Other income-net	(2,551)	(2,145)
Income before income taxes	77,157	68,337
Income tax expense	28,176	25,236
Net income	48,981	43,101
Net income attributable to noncontrolling interests	(482)	(760)
Net income attributable to Avista Corporation shareholders	$ 48,499	$ 42,341
Weighted-average common shares outstanding (thousands), basic	60,122	59,866
Weighted-average common shares outstanding (thousands), diluted	60,168	59,898
Earnings per common share attributable to Avista Corporation shareholders:
Basic (usd per share)	$ 0.81	$ 0.71
Diluted (usd per share)	$ 0.81	$ 0.71