Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement of Other Comprehensive Income [Abstract]
Net income	$ 25,730	$ 18,532	$ 68,831	$ 56,745
Other Comprehensive Income (Loss):
Unrealized investment gains - net of taxes	(1,222)	230	(1,292)	299
Reclassification adjustment for realized gains on investment securities included in net income - net of taxes	(10)	(130)	(11)	(141)
Change in unfunded benefit obligation for pension and other postretirement benefit plans - net of taxes	183	168	367	321
Total other comprehensive loss	(1,049)	268	(936)	479
Comprehensive income	24,681	18,800	67,895	57,224
Comprehensive income attributable to noncontrolling interests	(73)	(354)	(833)	(179)
Comprehensive income attributable to Avista Corporation shareholders	$ 24,608	$ 18,446	$ 67,062	$ 57,045

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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