Note 6 - Employee Benefit Plans - Fair Value by Asset Category (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Total fair value	$ 189,874	$ 148,052	$ 116,067
Hecla Mining Company Retirement Plan [Member]
Total fair value	160,272	120,384
Lucky Friday Pension Plan [Member]
Total fair value	29,602	27,668
Fair Value, Inputs, Level 1 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	107,661	84,308
Fair Value, Inputs, Level 1 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	17,592	19,100
Fair Value, Inputs, Level 2 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Fair Value, Inputs, Level 2 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Fair Value, Inputs, Level 3 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Fair Value, Inputs, Level 3 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Fair Value, Inputs, Level 1, 2 and 3 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	107,661	84,308
Fair Value, Inputs, Level 1, 2 and 3 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	17,592	19,100
Fair Value Measured at Net Asset Value Per Share [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	52,611	36,076
Fair Value Measured at Net Asset Value Per Share [Member] | Lucky Friday Pension Plan [Member]
Total fair value	12,010	8,568
Interest-bearing Deposits [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	1,835	367
Interest-bearing Deposits [Member] | Lucky Friday Pension Plan [Member]
Total fair value	305	111
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	1,835	367
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	305	111
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 3 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 3 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Common Stock [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	8,869	13,947
Common Stock [Member] | Lucky Friday Pension Plan [Member]
Total fair value	1,580	3,203
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	8,869	13,947
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	1,580	3,203
Common Stock [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Common Stock [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Common Stock [Member] | Fair Value, Inputs, Level 3 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Common Stock [Member] | Fair Value, Inputs, Level 3 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Mutual Funds [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	96,957	69,994
Mutual Funds [Member] | Lucky Friday Pension Plan [Member]
Total fair value	15,707	15,786
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	96,957	69,994
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	15,707	15,786
Mutual Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Mutual Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Mutual Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	0	0
Mutual Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Lucky Friday Pension Plan [Member]
Total fair value	0	0
Real Estate Investments [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	19,119	12,708
Real Estate Investments [Member] | Lucky Friday Pension Plan [Member]
Total fair value	4,482	3,428
Hedge Funds [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	12,866	5,823
Hedge Funds [Member] | Lucky Friday Pension Plan [Member]
Total fair value	2,828	1,215
Common Collective Funds [Member] | Hecla Mining Company Retirement Plan [Member]
Total fair value	20,626	17,545
Common Collective Funds [Member] | Lucky Friday Pension Plan [Member]
Total fair value	$ 4,700	$ 3,925