Note 13 - Accrued Liabilities - Components of Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Contract liabilities (Note 3)	$ 694	$ 850
Accrued remediation contingency (Note 14)	11	176
Other accrued liabilities	634	1,073
Total other accrued liabilities	$ 1,339	$ 2,099

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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