Property, Plant and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, Plant and Equipment

	As of December 31
(Dollars in millions)	2021		2020		Estimated life (years)
Machinery and equipment	852		825		3-8
Buildings	130		134		20
Construction in progress	36		63		n/a
Property, plant and equipment	$	1,018	$	1,022
Less accumulated depreciation	(649)		(591)
Net of accumulated depreciation	$	369	$	431
	Year Ended December 31
DEPRECIATION INCLUDED IN (Dollars in millions)	2021		2020		2019
Cost of sales	$	63	$	54	$	59
Selling, general and administrative expenses	5		4		4
Research, development and engineering expenses, net	39		39		32
Total	$	107	$	97	$	95

The net book value of machinery, equipment, buildings and land under finance lease contracts was $45 million and $47 million as of December 31, 2021 and 2020, respectively.