
	Oilfield Services & Equipment		Industrial & Energy Technology		Total
Balance at December 31, 2021, gross	$	19,531	$	4,661	$	24,192
Accumulated impairment at December 31, 2021	(18,217)		(254)		(18,471)
Balance at December 31, 2021	1,314		4,407		5,721

Disposition	(161)		—		(161)
Acquisitions	41		417		458
Currency exchange, impairment and other	—		(96)		(96)
Total	1,194		4,728		5,922
Classified as held for sale (1)	—		(230)		(230)
Balance at December 31, 2022	1,194		4,498		5,691


Currency exchange and other	16		(30)		(14)
Balance at March 31, 2023	$	1,210	$	4,468	$	5,677

(1)The reduction in Industrial & Energy Technology ("IET") goodwill relates to transferring our IET Nexus Controls business to held for sale. See "Note 17. Business Held for Sale" for further information.

We perform our annual goodwill impairment test for each of our reporting units as of July 1 of each fiscal year, in conjunction with our annual strategic planning process. We also test goodwill for impairment whenever events or circumstances occur which, in our judgment, could more likely than not reduce the fair value of one or more reporting units below its carrying value. Potential impairment indicators include, but are not limited to, (i) the results of our most recent annual or interim impairment testing, in particular the magnitude of the excess of fair value over carrying value observed, (ii) downward revisions to internal forecasts, and the magnitude thereof, if any, and (iii) declines in Baker Hughes' market capitalization below its book value, and the magnitude and duration of those declines, if any.

During the first quarter of 2023, we completed a review to assess whether indicators of impairment existed. As a result of this assessment, we concluded that no indicators existed that would lead to a determination that it is more likely than not that the fair value of each reporting unit is less than its carrying value. There can be no assurances that future sustained declines in macroeconomic or business conditions affecting our industry will not occur, which could result in goodwill impairment charges in future periods.


	March 31, 2023						December 31, 2022
	Gross Carrying Amount		Accumulated Amortization		Net		Gross Carrying Amount		Accumulated Amortization		Net
Customer relationships	$	1,898	$	(746)	$	1,152	$	1,917	$	(729)	$	1,189
Technology	1,204		(816)		388		1,212		(803)		409
Trade names and trademarks	287		(178)		109		287		(175)		112
Capitalized software	1,325		(1,053)		272		1,308		(1,040)		268


Finite-lived intangible assets	4,714		(2,793)		1,921		4,725		(2,747)		1,978
Indefinite-lived intangible assets	2,202		—		2,202		2,202		—		2,202
Total intangible assets	$	6,916	$	(2,793)	$	4,123	$	6,927	$	(2,747)	$	4,180

Intangible assets are generally amortized on a straight-line basis with estimated useful lives ranging from 1 to 35 years. Amortization expense for the three months ended March 31, 2023 and 2022 was $63 million and $55 million, respectively.