Note 5. Goodwill and Identifiable Intangibles

Changes in the carrying amount of goodwill are as follows (in thousands):



	Gross Value		Accumulated Impairment		Net
At December 31, 2018	$	177,115	$	(154,003)	$	23,112
Impairment		—		(7,937)		(7,937)
Currency translation adjustment		47		—		47
At December 31, 2019	$	177,162	$	(161,940)	$	15,222
Impairment		—		—		—
At June 30, 2020	$	177,162	$	(161,940)	$	15,222

We perform our annual impairment analysis of goodwill as of December 31, or when there is an indication an impairment may have occurred. As of March 31, 2020, we performed a quantitative impairment analysis for goodwill utilizing a market participant perspective and determined that the fair value exceeded the carrying value of our reporting unit. During the second quarter of 2020, we did not identify any triggering events for goodwill. Accordingly, there was no impairment charge recorded for goodwill for the three and six months ended June 30, 2020.

During the second quarter of 2019, we performed an impairment analysis for goodwill. Evidence of an indication of impairment included further deterioration in customer activity levels in North America, which resulted in lower demand for oilfield services driving a decrease in our market share and increased customer and competitor-driven pricing pressures in addition to a decline in the quoted price of our common stock. We determined that the carrying value of one of our reporting units exceeded its fair value and we recorded an impairment charge of $7.9 million for our tracer diagnostic services reporting unit. Following the impairment, our tracer diagnostic services reporting unit had no remaining goodwill balance as of June 30, 2019. There was no indication an impairment may have occurred in any other reporting unit for the three and six months ended June 30, 2019.

Identifiable intangibles by major asset class consist of the following (in thousands):



		June 30, 2020
	Estimated	Gross
	Useful	Carrying		Accumulated		Net
	Lives (Years)	Amount		Amortization		Balance
Technology	1 - 18	$	109	$	(63)	$	46
Customer relationships	10		4,100		(1,401)		2,699
Total identifiable intangibles		$	4,209	$	(1,464)	$	2,745



		December 31, 2019
	Estimated	Gross
	Useful	Carrying		Accumulated		Net
	Lives (Years)	Amount		Amortization		Balance
Technology	8 - 18	$	17,721	$	(2,380)	$	15,341
Trademarks	5 - 10		1,600		(373)		1,227
Customer relationships	10 - 21		28,689		(3,928)		24,761
Internally developed software	5		4,904		(985)		3,919
Total identifiable intangibles		$	52,914	$	(7,666)	$	45,248

Total amortization expense, which is associated with the selling, general and administrative expenses income statement line item, was $0.1 million and $1.1 million for the three months ended June 30, 2020 and 2019, respectively, and $1.2 million and $2.3 million for the six months ended June 30, 2020 and 2019, respectively.

Identifiable intangibles with definite lives are tested for impairment whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. On March 31, 2020, we evaluated our finite-lived intangible assets for impairment due to current industry conditions including a reduction in global economic growth expectations, a significantly reduced demand for crude oil and refined products, the significant decline in commodity prices and the corresponding impact on future expectations of demand for our products and services primarily related to the COVID-19 pandemic as well as the resulting decline in the quoted price of our common stock. As a result of the analysis, we determined that the carrying values of certain intangible assets were no longer recoverable, which resulted in an impairment charge of $11.9 million in the asset group that includes fracturing systems and well construction related to technology and internally-developed software and an impairment charge of $28.6 million in our tracer diagnostics asset group related to customer relationships, technology, internally developed software and trademarks, each recorded on March 31, 2020. Following the impairment charges in the first quarter of 2020, we had no remaining identifiable intangible balances in the asset group that includes our fracturing systems and well construction or our tracer diagnostics asset group. There were no impairment charges recorded for our identifiable intangibles for the three months ended June 30, 2020 and 2019.