Note 8 - Derivative Instruments (Tables)

6 Months Ended

Jun. 30, 2022

Notes Tables

Schedule of Foreign Exchange Contracts, Statement of Financial Position [Table Text Block]

	June 30,		December 31,
	2022		2021
Balance sheet line item:
Current derivatives assets	$	1.1	$	2.7
Non-current derivatives assets		1.3		2.5
Current derivative liabilities		0.3		—
Non-current derivative liabilities		0.2		—

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

June 30, 2022	Ounces/pounds under contract (in 000's)								Average price per ounce/pound
	Silver		Gold		Zinc		Lead		Silver		Gold		Zinc		Lead
	(ounces)		(ounces)		(pounds)		(pounds)		(ounces)		(ounces)		(pounds)		(pounds)
Contracts on provisional sales
2022 settlements		1,729		3		6,504		3,638	$	22.19	$	1,836	$	1.58	$	0.90
Contracts on forecasted sales
2022 settlements		—		—		38,030		34,778		N/A		N/A	$	1.31	$	0.98
2023 settlements		—		—		78,264		75,618		N/A		N/A	$	1.30	$	1.00
2024 settlements		—		—		78,760		31,526		N/A		N/A	$	1.34	$	1.01
2025 settlements		—		—		1,157		—		N/A		N/A	$	1.37		N/A

December 31, 2021	Ounces/pounds under contract (in 000's)								Average price per ounce/pound
	Silver		Gold		Zinc		Lead		Silver		Gold		Zinc		Lead
	(ounces)		(ounces)		(pounds)		(pounds)		(ounces)		(ounces)		(pounds)		(pounds)
Contracts on provisional sales
2022 settlements		1,814		6		13,371		4,575	$	23.02	$	1,812	$	1.39	$	0.96
Contracts on forecasted sales
2022 settlements		—		—		57,706		59,194		N/A		N/A	$	1.28	$	0.98
2023 settlements		—		—		76,280		71,650		N/A		N/A	$	1.29	$	1.00

Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block]

	June 30, 2022								December 31, 2021
	Contracts in an asset position		Contracts in a liability position			Net asset (liability)			Contracts in an asset position		Contracts in a liability position			Net asset (liability)
Balance sheet line item:
Current derivatives assets	$	8.8	$	—		$	8.8		$	—	$	—		$	—
Non-current derivative assets	$	11.6	$	—			11.6		$	—	$	—		$	—
Current derivatives liabilities		—		(3.9	)		(3.9	)		0.7		(20.1	)		(19.4	)
Non-current derivatives liabilities		—		(0.4	)		(0.4	)		0.4		(18.9	)		(18.5	)