Note 13. 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
	April 1, 2017		March 26, 2016
Total net revenues^(1):
South Korea	$	18,619	$	8,436
United States		13,573		7,191
Taiwan		11,833		5,477
China		6,687		6,506
Japan		3,353		7,188
Singapore		1,491		9,902
Other		3,758		2,789
Total net revenues	$	59,314	$	47,489

	April 1, 2017		December 31, 2016
Long-lived tangible assets:
United States	$	41,659	$	42,688
International		1,517		1,538
Total long-lived tangible assets	$	43,176	$	44,226

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

	At
	April 1, 2017		December 31, 2016
SK Hynix		22.0%	***
Taiwan Semiconductor Manufacturing Company Limited		20.0%		20.1%
Samsung Electronics Co. Ltd.		13.4%		14.3%
Micron Technology, Inc.	***			11.8%
Intel Corporation	***			11.1%
Toshiba Corporation	***			10.2%

***	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
	April 1, 2017		March 26, 2016
Samsung Electronics Co. Ltd.		21.6%	***
Taiwan Semiconductor Manufacturing Company Limited		16.7%		10.1%
Intel Corporation		15.6%		15.7%
SK Hynix		13.6%		16.7%
Micron Technology, Inc.	***			25.9%
Toshiba Corporation	***			11.9%

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