CONCENTRATION OF RISK: (Tables)

12 Months Ended

Dec. 31, 2023

CONCENTRATION OF RISK:

Schedule of concentration risk for cash equivalents and short- term investments

	$ in		% of total		% in one institution
Country	million		cash (1)		of country		of total cash
United States	$	1,294.9	74.0	%	14.7	%	10.9	%
Canada		122.0	7.0	%	100.0	%	7.0	%
Switzerland		222.3	12.7	%	100.0	%	12.7	%
Peru		26.5	1.5	%	87.8	%	1.3	%
Mexico		85.1	4.8	%	87.1	%	4.2	%
Total cash and short-term investment	$	1,750.8	100.0	%

(1) 98.0% of the Company’s cash is in U.S. dollars.

Schedule of company's largest customers as percentage of accounts receivable and total sales

	2023		2022		2021
Accounts receivable trade as of December 31,
Five largest customers	32.6	%	34.2	%	31.3	%
Largest customer	9.7	%	10.4	%	11.8	%
Total sales in year
Five largest customers	24.7	%	25.7	%	25.0	%
Largest customer	7.7	%	6.8	%	7.2	%