Note 11. Segment Information and Foreign Operations

Segment Information

We operate in one segment for the design, development, manufacture and distribution of high-performance compound and single element semiconductor substrates and sale of raw materials integral to these substrates. In accordance with ASC Topic 280, Segment Reporting, our chief operating decision-maker has been identified as our Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing performance for the Company. Since we operate in one segment, all financial segment and product line information can be found in the condensed consolidated financial statements.

Product Information

The following table represents revenue amounts (in thousands) by product type:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Product Type:
Substrates	$	22,802	$	22,377	$	63,769	$	58,095
Raw Materials and Others		5,824		5,791		16,396		14,246
Total	$	28,626	$	28,168	$	80,165	$	72,341

Geographical Information

The following table represents revenue amounts (in thousands) reported for products shipped to customers in the corresponding geographic region:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Geographical region:
China	$	10,268	$	7,203	$	26,271	$	17,949
Taiwan		6,116		5,986		15,445		13,499
Europe (primarily Germany)		4,879		6,192		17,957		17,638
North America (primarily the United States)		2,967		2,159		7,052		5,909
Asia Pacific (excluding China, Taiwan and Japan)		2,334		2,934		6,399		7,650
Japan		2,062		3,694		7,041		9,696
Total	$	28,626	$	28,168	$	80,165	$	72,341

Long-lived assets consist primarily of property, plant and equipment, and are attributed to the geographic location in which they are located. Long-lived assets, net of depreciation, by geographic region were as follows (in thousands):


	As of
	September 30,		December 31,
	2018		2017
Long-lived assets by geographic region, net of depreciation:
North America	$	542	$	1,410
China		74,212		45,120
	$	74,754	$	46,530

Significant Customers

One customer, Landmark, represented 16% of our revenue for the three months ended September 30, 2018 while two customers, Landmark and Osram Opto, represented 16% and 10%, respectively, of our revenue for the three months ended September 30, 2017. Our top five customers, although not the same five customers for each period, represented 39% and 39% of our revenue for the three months ended September 30, 2018 and 2017, respectively.

One customer, Landmark, represented 13% of our revenue for the nine months ended September 30, 2018 while two customers, Landmark and Osram Opto, represented 12% and 11%, respectively, of our revenue for the nine months ended September 30, 2017. Our top five customers, although not the same five customers for each period, represented 36% and 37% of our revenue for the nine months ended September 30, 2018 and 2017, respectively.

We perform ongoing credit evaluations of our customers’ financial condition, and limit the amount of credit extended when deemed necessary, but generally do not require collateral. Three customers accounted for 15%, 14% and 11% of our accounts receivable balance as of September 30, 2018, and one customer accounted for 12% of our accounts receivable balance as of December 31, 2017.