CONCENTRATION OF RISK

9 Months Ended

Sep. 30, 2022

19. CONCENTRATION OF RISK:

Revenues and accounts receivable from the Company's largest customers were as follows (in thousands):


	% of Total Revenue for the Three Months Ended September 30,		% of Total Revenue for the Nine Months Ended September 30,		Accounts Receivable as of
Customer	2022	2021	2022	2021	September 30, 2022
A	46%	50%	42%	46%	$	10,354
B	23%	27%	26%	25%	$	28,677
C	12%	7%	14%	14%	$	9,548

Revenues from outside of North America represented approximately 97% for both three-month and nine-month periods ended September 30, 2022 and 2021. Revenues by geographic area are as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Country	2022		2021		2022		2021
South Korea	$	100,555	$	95,741	$	269,338	$	250,040
China		52,906		41,323		159,486		138,135
Japan		2,011		1,911		4,456		5,227
Other non-U.S. locations		976		537		1,991		2,257
Total non-U.S. locations		156,448		139,512		435,271		395,659
United States		4,108		4,106		12,316		11,619
Total revenue	$	160,556	$	143,618	$	447,587	$	407,278

The Company attributes revenue to different geographic areas on the basis of the location of the customer.

Long-lived assets (net), by geographic area are as follows (in thousands):


	September 30, 2022		December 31, 2021
United States	$	115,282	$	115,004
Ireland	$	16,695	$	7,000
Other		5,736		6,828
Total long-lived assets	$	137,713	$	128,832

Substantially all chemical materials were purchased from one supplier. See Note 13 for further explanation.