Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Reconciliation of Intangible Assets

The reconciliation of intangible assets for the six months ended June 30, 2022 and 2021 (in thousands) was as follows:

	June 30,			June 30,
	2022			2021
Patented technologies
Gross carrying amount at beginning of period	$	68,322		$	68,322
Gross carrying amount at end of period		68,322			68,322
Accumulated amortization at beginning of period		(45,573	)		(43,113	)
Amortization expense		(1,230	)		(1,230	)
Accumulated amortization at end of period		(46,803	)		(44,343	)
Net book value at end of period	$	21,519		$	23,979