CONCENTRATION OF RISK

6 Months Ended

Jun. 30, 2018

14.	CONCENTRATION OF RISK:

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

	% of Revenues for the three months ended June 30,		% of Revenues for the six months ended June 30,		Accounts Receivable as of
Customer	2018	2017	2018	2017	June 30, 2018
A	42%	17%	48%	23%	$	15,199
B	33%	73%	26%	66%	$	3,811
C	9%	1%	9%	1%	$	4,304

Revenues from outside of North America represented approximately 93% and 98% of consolidated revenue for the three months ended June 30, 2018 and 2017, respectively, and 94% and 97% of consolidated revenue for the six months ended June 30, 2018 and 2017, respectively. Revenues by geographic area are as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
Country	2018		2017		2018		2017
South Korea	$	42,132	$	92,206	$	72,906	$	140,134
China		8,479		5,414		17,331		7,896
Japan		686		2,044		1,561		3,128
Other non-U.S. locations		1,061		822		1,622		1,534
Total non-U.S. locations	$	52,358	$	100,486	$	93,420	$	152,692
United States		3,791		2,027		6,301		5,387
Total revenue	$	56,149	$	102,513	$	99,721	$	158,079

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):

	June 30, 2018		December 31, 2017
United States	$	59,483	$	53,991
Other		2,865		2,459
Total long-lived assets	$	62,348	$	56,450

Substantially all chemical materials were purchased from one supplier. See Note 8.