Property, plant and equipment (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of Useful Lives of Assets

The useful lives of these assets are generally as follows:

	Years
Buildings	25 to 33
Plant and equipment	1 to 10
Instrumentation	3 to 4
Computer software	3 to 7
Furniture and fixtures	4 to 8

Schedule of Property, Plant and Equipment

The assets and related accumulated depreciation are adjusted for property retirements and disposals, with the resulting gain or loss included in earnings. Fully depreciated assets remain in the accounts until retired from service.

	December 31,
(U.S. Dollars, in thousands)	2022			2021
Cost
Buildings	$	3,867		$	3,925
Plant and equipment		48,358			50,275
Instrumentation		92,607			100,515
Computer software		40,685			53,200
Furniture and fixtures		7,917			8,307
Construction in progress		4,515			2,597
Finance lease assets		23,276			23,397
Property, plant, and equipment, gross		221,225			242,216
Accumulated depreciation		(162,996	)		(182,964	)
Property, plant, and equipment, net	$	58,229		$	59,252