CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
Beginning Balance (in shares) at Dec. 31, 2018		65,688,356
Shares issued through equity compensation plans		75,399
Shares issued through Employee Investment Plan (401-K)		3,653
Shares issued through sales agency agreements		1,409,588
Ending Balance (in shares) at Dec. 31, 2019		67,176,996
Beginning Balance at Dec. 31, 2018		$ 1,136,491	$ (7,866)	$ 644,595
Equity compensation expense		10,568
Issuance of common stock through equity compensation plans		827
Issuance of common stock through Employee Investment Plan (401-K)		175
Issuance of common stock through sales agency agreements, net of issuance costs		63,571
Payment of minimum tax withholdings for share-based payment awards		(891)
Ending Balance at Dec. 31, 2019	$ 1,939,284	$ 1,210,741	(10,259)	738,802
Other comprehensive income (loss)	(2,393)		(2,393)
Net income attributable to Avista Corporation shareholders	196,979			196,979
Dividends on common stock				(102,772)
Beginning Balance Noncontrolling Interest at Dec. 31, 2018					$ 825
Net loss attributable to noncontrolling interests	$ 216				(216)
Deconsolidation of noncontrolling interests related to sale of METALfx					$ (609)
Dividends declared per common share	$ 1.55
Total Avista Corporation shareholders’ equity	$ 1,939,284
Shares issued through equity compensation plans		139,726
Shares issued through Employee Investment Plan (401-K)		17,179
Shares issued through sales agency agreements		1,905,000
Ending Balance (in shares) at Dec. 31, 2020	69,238,901	69,238,901
Equity compensation expense		$ 5,535
Issuance of common stock through equity compensation plans		965
Issuance of common stock through Employee Investment Plan (401-K)		674
Issuance of common stock through sales agency agreements, net of issuance costs		70,561
Payment of minimum tax withholdings for share-based payment awards		(2,408)
Ending Balance at Dec. 31, 2020	$ 2,029,726	$ 1,286,068	(14,378)	758,036
Other comprehensive income (loss)	(4,119)		(4,119)
Net income attributable to Avista Corporation shareholders	$ 129,488			129,488
Dividends on common stock				(110,254)
Dividends declared per common share	$ 1.62
Total Avista Corporation shareholders’ equity	$ 2,029,726
Shares issued through equity compensation plans		93,806
Shares issued through Employee Investment Plan (401-K)		14,480
Shares issued through sales agency agreements		2,150,336
Ending Balance (in shares) at Dec. 31, 2021	71,497,523	71,497,523
Equity compensation expense		$ 5,079
Issuance of common stock through equity compensation plans		931
Issuance of common stock through Employee Investment Plan (401-K)		610
Issuance of common stock through sales agency agreements, net of issuance costs		88,457
Payment of minimum tax withholdings for share-based payment awards		(993)
Ending Balance at Dec. 31, 2021	$ 2,154,744	$ 1,380,152	(11,039)	785,631
Other comprehensive income (loss)	3,339		$ (3,339)
Net income attributable to Avista Corporation shareholders	$ 147,334			147,334
Dividends on common stock				$ (119,739)
Dividends declared per common share	$ 1.69
Total Avista Corporation shareholders’ equity	$ 2,154,744