Details of Selected Balance Sheet Accounts

Inventories



A summary of inventories follows (in thousands):	March 31, 2020			December 31, 2019
Raw materials and subassemblies	$	18,181		$	18,509
Work-in-process	2,340			2,079
Finished goods	5,518			4,932
Less: reserve for excess and obsolete inventories	(13,219		)	(13,333		)
Inventories, net	$	12,820		$	12,187

Property, Plant and Equipment



A summary of property, plant and equipment follows (in thousands):	March 31, 2020			December 31, 2019
Buildings	$	15,665		$	15,486
Machinery and equipment	133,722			133,048
Seismic rental equipment	1,668			1,669
Furniture and fixtures	3,158			3,347
Other	29,955			31,142
Total	184,168			184,692
Less: accumulated depreciation	(134,909		)	(134,951		)
Less: impairment of long-lived assets	(36,553		)	(36,553		)
Property, plant and equipment, net	$	12,706		$	13,188

Total depreciation expense, including amortization of assets recorded under equipment finance leases, for both the three months ended March 31, 2020 and 2019 was $0.8 million. No impairment charge was recognized during the three months ended March 31, 2020 and 2019.

Multi-Client Data Library



The change in multi-client data library are as follows (in thousands):	March 31, 2020			December 31, 2019
Gross costs of multi-client data creation	$	1,010,909		$	1,007,762
Less: accumulated amortization	(824,421		)	(816,401		)
Less: impairments to multi-client data library	(132,144		)	(130,977		)
Multi-client data library, net	$	54,344		$	60,384

Total amortization expense for the three months ended March 31, 2020 and 2019 was $8.0 million and $11.1 million, respectively. For the three months ended March 31, 2020, the Company recognized an impairment to multi-client data library of $1.2 million. No impairment to multi-client data library was recognized during the three months ended March 31, 2019.

Goodwill



	E&P Technology & Services		Optimization Software & Services			Total
Balance at January 1, 2019	$	2,943	$	19,972		$	22,915
Impact of foreign currency translation adjustments	—		670			670
Balance at December 31, 2019	2,943		20,642			23,585
Impairment of goodwill	—		(4,150		)	(4,150		)
Impact of foreign currency translation adjustments	—		(1,137		)	(1,137		)
Balance at March 31, 2020	$	2,943	$	15,355		$	18,298

The Company assessed the relevant events and circumstances in evaluating whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. During the quarter, markets for oil and gas, as well as other commodities and equities, have experienced significant volatility and price declines amid concerns over the economic effects of the COVID-19 pandemic. As a result, the Company’s stock price experienced a significant decline during the first quarter of 2020. Based on these facts, the Company performed a goodwill impairment test at March 31, 2020 to determine if it was more likely than not that the fair value of certain reporting units were less than their carrying value.

The Company compared the fair value of each reporting unit against its carrying value. If the carrying value of the reporting unit exceeds the fair value, an impairment loss shall be recognized in an amount equal to that excess. The fair value of each reporting unit at March 31, 2020 was determined using a discounted cash flow model. The Company utilized a discount rate of 19% for both reporting units. The Company used reasonable assumptions based on historical data supplemented by anticipated market conditions and estimated growth rates. However, given the uncertainty in determining the assumptions underlying a discounted cash flow analysis, actual results may differ which could result in additional impairment charge in the future.

The Company recorded an impairment charge of $4.2 million for the three months ended March 31, 2020 related to its Optimization Software & Services reporting unit, which is included within the Operations Optimization segment. No impairment charge was recognized for the E&P Technology Services reporting unit for the three months ended March 31, 2020.