Note 15. Segment, Geographic, Product and Significant Customer Information

The Company has one operating segment, which is the sale, design, manufacture, marketing and support of optical critical dimension and thin film systems. The following tables summarize total net revenues and long-lived assets (excluding intangible assets) attributed to significant countries (in thousands):

	Three Months Ended				Nine Months Ended
	September 24, 2016		September 26, 2015		September 24, 2016		September 26, 2015
Total net revenues^(1):
China	$	15,710	$	6,731	$	35,226	$	12,357
South Korea		11,765		6,794		24,669		28,807
United States		8,211		7,985		24,306		32,115
Singapore		7,364		2,988		33,883		15,875
Taiwan		6,334		11,331		16,962		35,173
Japan		5,078		7,778		18,645		15,919
Other		4,252		2,071		8,279		4,436
Total net revenues	$	58,714	$	45,678	$	161,970	$	144,682

	September 24, 2016		December 26, 2015
Long-lived tangible assets:
United States	$	42,603	$	42,581
International		1,721		1,912
Total long-lived tangible assets	$	44,324	$	44,493

The following customers accounted for 10% or more of total accounts receivable, net:

	At
	September 24, 2016			December 26, 2015
Taiwan Semiconductor Manufacturing Company Limited		20.0	%		25.6	%
Micron		15.3	%	***
Intel		13.6	%	***
United Semiconductor (Xiamen) Co., Ltd.		10.6	%	***
Toshiba Corporation	***				27.1	%

***	The customer accounted for less than 10% of total accounts receivable, net, as of that period end.

The following customers accounted for 10% or more of total net revenues:

	Three Months Ended						Nine Months Ended
	September 24, 2016			September 26, 2015			September 24, 2016			September 26, 2015
SK Hynix		18.8	%		15.0	%		14.0	%		13.0	%
Intel Corporation		18.5	%	***				19.4	%	***
Micron		14.6	%		14.0	%		25.2	%		18.0	%
Toshiba Corporation	***				13.0	%	***			***
Taiwan Semiconductor Manufacturing Company Limited	***				17.0	%	***				19.0	%
Samsung Electronics Co. Ltd.	***			***			***				16.0	%

***	The customer accounted for less than 10% of total net revenues during the period.