Note 11 - Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair value adjustments net

Fair value adjustments, net is comprised of the following (in thousands):

	Year Ended December 31,
	2023			2022			2021
Gain (loss) on derivative contracts	$	3,168		$	844		$	(32,655	)
Unrealized (loss) on investments in equity securities		(243	)		(5,632	)		(4,295	)
Gain on disposition or exchange of investments		—			65			1,158
Total fair value adjustments, net	$	2,925		$	(4,723	)	$	(35,792	)

Schedule of assets and liabilities at fair value on a recurring basis

The table below sets forth our assets and liabilities (in thousands) that were accounted for at fair value on a recurring basis and the fair value calculation input hierarchy level that we have determined applies to each asset and liability category. See Note 6 for information on the fair values of our defined benefit pension plan assets.

	Balance at December 31, 2023		Balance at December 31, 2022		Input Hierarchy Level
Assets:
Cash and cash equivalents:
Money market funds and other bank deposits	$	106,374	$	104,743	Level 1
Current and non-current investments:
Equity securities		32,284		24,018	Level 1
Trade accounts receivable:
Receivables from provisional concentrate sales		14,740		45,146	Level 2
Derivative contracts - other current assets and other non-current assets:
Metal forward contracts		4,698		1,309	Level 2
Foreign exchange contracts		4,657		1,518	Level 2
Restricted cash and cash equivalents balances:
Certificates of deposit and other deposits		1,165		1,164	Level 1
Total assets	$	163,918	$	177,898
Liabilities
Derivative contracts - current and non-current derivative liabilities:
Metal forward contracts	$	40	$	14,643	Level 2
Foreign exchange contracts		1,508		7,548	Level 2
Total liabilities	$	1,548	$	22,191