Segment, Geographic, Product and Significant Customer Information (Tables)

12 Months Ended

Dec. 30, 2017

Segment Reporting [Abstract]

Total net revenue

The following tables summarize total net revenues and long-lived assets (excluding intangible assets) attributed to significant countries (in thousands):

	Years Ended
	December 30, 2017		December 31, 2016		December 26, 2015
Total net revenues (1):
South Korea	$	94,082	$	44,735	$	30,572
China		29,826		43,460		17,373
Singapore		21,810		37,096		17,395
United States		33,983		29,887		36,720
Taiwan		20,147		27,189		46,715
Japan		41,979		26,604		31,140
Other		16,794		12,158		7,452
Total net revenues	$	258,621	$	221,129	$	187,367

⁽¹⁾ Net revenues are attributed to countries based on the customer's deployment and service locations of systems.

Long-lived tangible assets

	December 30, 2017		December 31, 2016
Long-lived tangible assets:
United States	$	43,427	$	42,688
Taiwan		510		818
South Korea		576		554
Japan		60		57
All Other		237		109
Total long-lived tangible assets	$	44,810	$	44,226

Revenues by product type

The Company’s product lines differ primarily based on the environment in which the systems will be used. Automated systems are used primarily in high-volume production environments. Materials characterization products are primarily used to measure the composition, band gap, structure, and other physical and electrical properties of semiconducting materials for discrete electronic industry, high brightness LED and solar/photovoltaic structures in both development and high-volume environments. Integrated systems are installed inside wafer processing equipment to provide near real-time measurements for improving process control and increasing throughput. Revenues by product type were as follows (in thousands): 

	Years Ended
	December 30, 2017		December 31, 2016		December 26, 2015
Automated Systems	$	151,401	$	127,378	$	102,386
Integrated Systems		42,183		43,846		31,579
Materials Characterization Systems		21,293		13,842		12,980
Total product revenues	$	214,877	$	185,066	$	146,945

Customers accounted for 10% or more of total accounts receivable

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

	Years Ended
	December 30, 2017			December 31, 2016			December 26, 2015
Taiwan Semiconductor Manufacturing Company Limited	***				20	%		26	%
Samsung Electronics Co. Ltd.		13	%		14	%	***
Micron Technology, Inc.		18	%		12	%	***
Intel Corporation	***				11	%	***
Toshiba Corporation		31	%		10	%		27	%

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

Customers accounted for 10% or more of total revenue

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

	Years Ended
	December 30, 2017			December 31, 2016			December 26, 2015
Samsung Electronics Co. Ltd.		26	%	***				13	%
SK Hynix		13	%		15	%		11	%
Micron Technology, Inc.		12	%		20	%		16	%
Intel Corporation		11	%		18	%	***
Toshiba Corporation		11	%	***				10	%
Taiwan Semiconductor Manufacturing Company Limited	***				10	%		19	%

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