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

12 Months Ended

Dec. 31, 2016

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 31, 2016		December 26, 2015		December 27, 2014
Total net revenues (1):
South Korea	$	44,735	$	30,572	$	41,381
China		43,460		17,373		28,702
Singapore		37,096		17,395		7,905
United States		29,887		36,720		36,123
Taiwan		27,189		46,715		19,790
Japan		26,604		31,140		15,185
Other		12,158		7,452		17,357
Total net revenues	$	221,129	$	187,367	$	166,443

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

Long-lived tangible assets

	December 31, 2016		December 26, 2015
Long-lived tangible assets:
United States	$	42,688	$	42,581
Taiwan		818		1,056
South Korea		554		697
Japan		57		59
All Other		109		100
Total long-lived tangible assets	$	44,226	$	44,493

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 31, 2016		December 26, 2015		December 27, 2014
Automated Systems	$	127,378	$	102,386	$	108,768
Integrated Systems		43,846		31,579		15,334
Materials Characterization Systems		13,842		12,980		9,487
Total product revenues	$	185,066	$	146,945	$	133,589

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 31, 2016			December 26, 2015			December 27, 2014
Taiwan Semiconductor Manufacturing Company Limited		20.1	%		25.6	%		20.2	%
Samsung Electronics Co. Ltd.		14.3	%	***				10.0	%
Micron Technology, Inc.		11.8	%	***				23.7	%
Intel Corporation		11.1	%	***			***
Toshiba Corporation		10.2	%		27.1	%	***
GLOBALFOUNDRIES	***			***				10.2	%

*** 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 31, 2016			December 26, 2015			December 27, 2014
Micron Technology, Inc.		20.3	%		15.8	%		10.4	%
Intel Corporation		18.0	%	***				12.6	%
SK Hynix		15.3	%		10.7	%		12.2	%
Taiwan Semiconductor Manufacturing Company Limited		10.0	%		19.4	%	***
Samsung Electronics Co. Ltd.	***				13.2	%		26.9	%
Toshiba Corporation	***				10.2	%	***

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