Inventory	12 Months Ended
Dec. 31, 2020
Inventory
Inventory	14. Inventory At each period end, inventory is reviewed to ensure that it is recorded at the lower of cost and net realizable value. Specific consideration was given to the valuation of the surplus government inventory. The Company determined that the valuation provision was not significant. During the year ended December 31, 2020, the Company recorded an inventory write-down of $1,691,000 (2019: $4,215,000; 2018: $1,011,000).

The entire disclosure for inventory. Includes, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the classes of inventory, and the nature of the cost elements included in inventory.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-URI http://asc.fasb.org/topic&trid=2126998

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