
	Offshore / Manufactured Products		Downhole Technologies		Well Site Services		Total
Balance as of December 31, 2019
Goodwill	$	162,750	$	357,502	$	244,349	$	764,601
Accumulated impairment losses	—		(165,000)		(117,295)		(282,295)
	162,750		192,502		127,054		482,306
Goodwill impairment (March 2020)	(86,500)		(192,502)		(127,054)		(406,056)
Foreign currency translation	239		—		—		239
Balance as of December 31, 2020	$	76,489	$	—	$	—	$	76,489

Balance as of December 31, 2020
Goodwill	$	162,989	$	357,502	$	244,349	$	764,840
Accumulated impairment losses	(86,500)		(357,502)		(244,349)		(688,351)
	76,489		—		—		76,489

Foreign currency translation	(77)		—		—		(77)
Balance as of December 31, 2021	$	76,412	$	—	$	—	$	76,412

Balance as of December 31, 2021
Goodwill	$	162,912	$	357,502	$	244,349	$	764,763
Accumulated impairment losses	(86,500)		(357,502)		(244,349)		(688,351)
	$	76,412	$	—	$	—	$	76,412

As further discussed in Note 2, "Summary of Significant Accounting Policies," goodwill is allocated to each reporting unit based on acquisitions made by the Company and is assessed for impairment annually and when an event occurs or circumstances change that indicate the carrying amounts may not be recoverable.

The Company had three reporting units – Offshore/Manufactured Products, Downhole Technologies and Well Site Services – whose goodwill balances totaled approximately $647 million as of September 30, 2019.

During the fourth quarter of 2019, U.S. land-based completion activity declined significantly from levels experienced over the previous three quarters. Additionally, a number of other market indicators declined to levels not experienced in recent years. Consistent with most other oilfield service industry peers, the Company's stock price declined and its market capitalization was below the carrying value of stockholders' equity. Given these market conditions, the Company reduced its near-term demand outlook for its short-cycle products and services in the U.S. shale play regions. This refined outlook was incorporated in the December 1, 2019 annual impairment assessment.

Management utilizes, depending on circumstances, a combination of valuation methodologies including a market approach and an income approach, as well as guideline public company comparables. The valuation techniques used in the December 1, 2019 assessment were consistent with those used during previous testing, except for the Downhole Technologies reporting unit where the income approach was used to estimate its fair value – with the market approach used only to validate the results in 2019. The fair value of the Company's reporting units were determined using significant unobservable inputs (a Level 3 fair value measurement).

The income approach estimates the fair value of each reporting unit by discounting the Company's current forecast of future cash flows by its estimate of the discount rate (or expected return) that a market participant would require. The market approach includes the use of comparative multiples to corroborate the discounted cash flow results. The market approach involves judgment in the selection of the appropriate peer group companies and valuation multiples.

Significant assumptions used in the income approach include, among others, the estimated future net annual cash flows and discount rates for each reporting unit. Management selected estimates used in the discounted cash flow projections using historical data as well as then-current and anticipated market conditions and estimated growth rates. These estimates were based upon assumptions that considered published industry trends and market forecasts of commodity prices, rig count, well count and offshore/onshore drilling and completion spending, and were believed to be reasonable at the time. The discount rates used to value the Company's reporting units as of December 1, 2019 ranged between 12.5% and 13.0%.

Based on this quantitative assessment, the Company concluded that the goodwill amount recorded in its Downhole Technologies reporting unit was partially impaired and recognized a non-cash goodwill impairment charge of $165.0 million in the fourth quarter of 2019.

Given the significance of the March 2020 events described in Note 3, "Asset Impairments and Other Charges," the Company performed a quantitative assessment of goodwill for further impairment as of March 31, 2020. This interim assessment indicated that the fair value of each of the reporting units was less than their respective carrying amounts due to, among other factors, the significant decline in the Company's stock price (and that of its peers) and reduced growth rate expectations given weak energy market conditions resulting from the demand destruction caused by the global response to the COVID-19 pandemic. In addition, the estimated returns required by market participants increased materially in the Company's March 31, 2020 assessment from the assessment performed as of December 1, 2019, resulting in higher discount rates used in the discounted cash flow analysis.

The valuation techniques used in the March 31, 2020 assessment were consistent with those used during the December 1, 2019 assessment, except for the Completion Services reporting unit where the income approach was used to estimate its fair value – with the market approach used only to validate the results in the March 2020 assessment. The fair value of the Company's reporting units were determined using significant unobservable inputs (a Level 3 fair value measurement).

Significant assumptions and estimates used in the income approach include, among others, estimated future net annual cash flows and discount rates for each reporting unit, current and anticipated market conditions, estimated growth rates and historical data. These estimates relied upon significant management judgment, particularly given the uncertainties regarding the COVID-19 pandemic and its impact on activity levels and commodity prices as well as future global economic growth. The discount rates used to value the Company's reporting units as of March 31, 2020 ranged between 16.8% and 18.5%.

Based on this quantitative assessment as of March 31, 2020, the Company concluded that goodwill recorded in the Completion Services and Downhole Technologies businesses was fully impaired while goodwill recorded in the Offshore/Manufactured Products business was partially impaired. The Company therefore recognized non-cash goodwill impairment charges totaling $406.1 million in the first quarter of 2020, as presented in further detail in the table above.

As of December 1, 2020 and 2021, the Company had only one reporting unit – Offshore/Manufactured Products – with a goodwill balance of $76 million. The Company performed its annual quantitative assessments of goodwill for impairment, which indicated that the fair value of the Offshore/Manufactured Products reporting unit was greater than its carrying amount and no additional impairment was required in either period. The fair value of the Offshore/Manufactured Products reporting unit was determined using significant unobservable inputs (a Level 3 fair value measurement).

The valuation techniques used in these annual assessments were consistent with those used during the March 31, 2020 assessment. The discount rate used to value the Offshore/Manufactured Products reporting unit as of December 1, 2020 and 2021 was 15.3% and 14.5%, respectively. The estimated returns required by market participants decreased in the Company's 2020 and 2021 annual assessments from the assessment as of March 31, 2020 given improvements in the global economy and financial markets.

The following table presents the gross carrying amount and the related accumulated amortization for major intangible asset classes as of December 31, 2021 and 2020 (in thousands):


	2021						2020
	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Other intangible assets:
Customer relationships	$	168,284	$	66,734	$	101,550	$	168,288	$	55,380	$	112,908
Patents/Technology/Know-how	78,821		33,151		45,670		75,920		26,124		49,796
Noncompete agreements	—		—		—		16,044		14,742		1,302
Tradenames and other	53,708		15,179		38,529		53,708		11,965		41,743
	$	300,813	$	115,064	$	185,749	$	313,960	$	108,211	$	205,749

Amortization expense was $20.6 million, $24.9 million and $26.8 million in the years ended December 31, 2021, 2020 and 2019, respectively. The weighted average remaining amortization period for all intangible assets, other than goodwill, was 11.3 years as of December 31, 2021 and 12.4 years as of December 31, 2020. Amortization expense is expected to total approximately $20 million in 2022 and $17 million in 2023 through 2026.