Note 8. Employee Benefit Plans (Detail) - Fair Value By Asset Category (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla [Member]
Assets at fair value	$ 609	$ 1,495
Interest-bearing Deposits [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday [Member]
Assets at fair value	166	466
Interest-bearing Deposits [Member] | Hecla [Member]
Assets at fair value	609
Interest-bearing Deposits [Member] | Hecla [Member]
Assets at fair value		1,495
Interest-bearing Deposits [Member] | Lucky Friday [Member]
Assets at fair value	166	466
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla [Member]
Assets at fair value	2,071	4,460
Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday [Member]
Assets at fair value	527	1,135
Common Stock [Member] | Hecla [Member]
Assets at fair value	2,071
Common Stock [Member] | Hecla [Member]
Assets at fair value		4,460
Common Stock [Member] | Lucky Friday [Member]
Assets at fair value	527	1,135
Closely Held Instruments [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla [Member]
Assets at fair value	2,777	3,660
Closely Held Instruments [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday [Member]
Assets at fair value	738	994
Closely Held Instruments [Member] | Fair Value, Inputs, Level 3 [Member] | Hecla [Member]
Assets at fair value	13,300	12,508
Closely Held Instruments [Member] | Fair Value, Inputs, Level 3 [Member] | Lucky Friday [Member]
Assets at fair value	3,566	3,356
Closely Held Instruments [Member] | Hecla [Member]
Assets at fair value	16,077
Closely Held Instruments [Member] | Hecla [Member]
Assets at fair value		16,168
Closely Held Instruments [Member] | Lucky Friday [Member]
Assets at fair value	4,304	4,350
Partnership/Joint Venture Interests [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla [Member]
Assets at fair value	1,836	3,360
Partnership/Joint Venture Interests [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday [Member]
Assets at fair value	523	935
Partnership/Joint Venture Interests [Member] | Hecla [Member]
Assets at fair value	1,836
Partnership/Joint Venture Interests [Member] | Hecla [Member]
Assets at fair value		3,360
Partnership/Joint Venture Interests [Member] | Lucky Friday [Member]
Assets at fair value	523	935
Common Collective Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Hecla [Member]
Assets at fair value	8,028	4,305
Common Collective Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Lucky Friday [Member]
Assets at fair value	2,049	1,109
Common Collective Funds [Member] | Hecla [Member]
Assets at fair value	8,028
Common Collective Funds [Member] | Hecla [Member]
Assets at fair value		4,305
Common Collective Funds [Member] | Lucky Friday [Member]
Assets at fair value	2,049	1,109
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Hecla [Member]
Assets at fair value	22,667	25,882
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Lucky Friday [Member]
Assets at fair value	6,225	6,797
Mutual Funds [Member] | Hecla [Member]
Assets at fair value	22,667
Mutual Funds [Member] | Hecla [Member]
Assets at fair value		25,882
Mutual Funds [Member] | Lucky Friday [Member]
Assets at fair value	6,225	6,797
Fair Value, Inputs, Level 1 [Member] | Hecla [Member]
Assets at fair value	25,347	31,837
Fair Value, Inputs, Level 1 [Member] | Lucky Friday [Member]
Assets at fair value	6,918	8,398
Fair Value, Inputs, Level 2 [Member] | Hecla [Member]
Assets at fair value	12,641	11,325
Fair Value, Inputs, Level 2 [Member] | Lucky Friday [Member]
Assets at fair value	3,310	3,038
Fair Value, Inputs, Level 3 [Member] | Hecla [Member]
Assets at fair value	13,300	12,508
Fair Value, Inputs, Level 3 [Member] | Lucky Friday [Member]
Assets at fair value	3,566	3,356
Hecla [Member]
Assets at fair value	51,288
Hecla [Member]
Assets at fair value		55,670
Lucky Friday [Member]
Assets at fair value	$ 13,794	$ 14,792