5. INTANGIBLES

We had no intangible assets as of December 31, 2016. In conjunction with the Merger, we recorded intangible assets of $21.1 million. As of December 31, 2017 our intangible assets consisted of the following:


	Dollars in Thousands
	December 31, 2017
	Cost		Accumulated Amortization		Net Book Value
Technology	$	18,990	$	475	$	18,515
Customer relationships	250		42		208
Backlog	200		100		100
Covenants not to compete	30		15		15
Trademark	40		10		30
IPR&D	1,590		—		1,590
	$	21,100	$	642	$	20,458


	Estimated Useful Life
Technology	20 years
Customer relationships	3 years
Backlog	1 year
Covenants not to compete	1 year
Trademark	2 years

Until our in-process research and development projects are completed, the assets are accounted for as indefinite-lived intangible assets and subject to impairment testing. For the year ended December 31, 2017, there was no impairment of IPR&D.

Amortization expense for intangible assets was $0.6 million during the year ended December 31, 2017. Amortization expense for intangible assets is expected to be $1.2 million, $1.0 million, $1.0 million, $0.9 million and $0.9 million for each of the years ending December 31, 2018, 2019, 2020, 2021 and 2022, respectively.