Note 12 - Commitments and Contingencies	6 Months Ended
Jun. 30, 2023
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	*Note 12.* Commitments and Contingencies Office Leases** We have long-term operating leases for office, industrial and laboratory space in Westminster, California, Oak Ridge, Tennessee, and Alberta, Canada. Payments made under operating leases are charged to the Consolidated Statement of Operations and Comprehensive Loss on a straight-line basis over the term of the operating lease agreement. Short-term leases less than one-year are not included in our analysis. For the three and six months ended June 30, 2023, rental expense was $83,000 and $166,000 and for the three and six months ended June 30, 2022, rental expense was $106,000 and $169,000. The lease of our Westminster facility expires August 2024. Management has not yet determined whether it will exercise its option to extend the lease four years; therefore the four-year extension is not included in the analysis. In September 2022, the lease of our Oak Ridge, Tennessee facility was extended for ten years. The lease of our Canadian facility is less than one year. None of our leases have additional terms related to the payments or mechanics of the lease. The leases have no additional payment terms such as common area maintenance payments, tax sharing payments or other allocable expenses. Likewise, the leases do not contain other terms and conditions of use, such as variable lease payments, residual value guaranties or other restrictive financial terms. Since there is no explicit interest rate in our leases, management used its incremental borrowing rate, which is estimated to be 18% to determine lease liability.

Note 12 - Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Text Block]

Note 12. Commitments and Contingencies

Office Leases

We have long-term operating leases for office, industrial and laboratory space in Westminster, California, Oak Ridge, Tennessee, and Alberta, Canada. Payments made under operating leases are charged to the Consolidated Statement of Operations and Comprehensive Loss on a straight-line basis over the term of the operating lease agreement. Short-term leases less than one-year are not included in our analysis. For the three and six months ended June 30, 2023, rental expense was $83,000 and $166,000 and for the three and six months ended June 30, 2022, rental expense was $106,000 and $169,000. The lease of our Westminster facility expires August 2024. Management has not yet determined whether it will exercise its option to extend the lease four years; therefore the four-year extension is not included in the analysis. In September 2022, the lease of our Oak Ridge, Tennessee facility was extended for ten years. The lease of our Canadian facility is less than one year. None of our leases have additional terms related to the payments or mechanics of the lease. The leases have no additional payment terms such as common area maintenance payments, tax sharing payments or other allocable expenses. Likewise, the leases do not contain other terms and conditions of use, such as variable lease payments, residual value guaranties or other restrictive financial terms. Since there is no explicit interest rate in our leases, management used its incremental borrowing rate, which is estimated to be 18% to determine lease liability.