Quarterly report pursuant to Section 13 or 15(d)

Intangible assets, royalties, and goodwill - Additional information (Details)

v3.21.1
Intangible assets, royalties, and goodwill - Additional information (Details) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]      
Amortization expense $ 400,000 $ 400,000  
Goodwill 18,614,000   $ 18,614,000
Goodwill, accumulated impairment loss 0   $ 0
Goodwill, impairment expense $ 0 $ 0  
Weighted Average      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful lives of intangible assets 10 years