XML 48 R37.htm IDEA: XBRL DOCUMENT v3.19.1
Patent Licenses - Summary of Future Amortization Expense Related to Intangible Assets Subject to Amortization (Detail)
$ in Thousands
Mar. 31, 2019
USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]  
2019 (Remaining nine months) $ 72
2020 91
2021 91
2022 91
2023 91
Thereafter 2,181
Total $ 2,617