Property, Plant and Equipment
 12 Months Ended
Dec. 31, 2021
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment Note 8 – Property, Plant and Equipment Property, plant and equipment improvements consist of the following (in thousands): December 31, 2021 2020 Computer hardware and software $ 1,008 $ 921Lab and factory equipment 21,100 20,554Furniture, fixtures and office equipment 59 59Finance lease - equipment 116 116Finance lease - manufacturing facility 12,968 12,706Construction in progress 11,804 1,734Leasehold improvements 151 128Factory Equipment - Gov't Award 1,170 -Total property, plant and equipment 48,376 36,218Less: accumulated depreciation and amortization (17,893) (15,086)Property, plant and equipment, net $ 30,483 $ 21,132 Depreciation and amortization expense was $2.8 million and $2.1 million for years ended December 31, 2021 and 2020. Amortization expense was $622 thousand and $68 thousand for assets under finance leases for the years ended December 31, 2021 and 2020. During 2020, the Company expanded its manufacturing space and signed a 10-year renewal of the related lease agreement, with two five year options to renew. The present value of the related lease payment exceeded 90% of the fair value of the underlying asset, classifying this as a finance lease. Formerly, the lease was classified as an operating lease and right of use asset.