Patents and Other Intangible Assets - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Patents	$ 1,050	$ 1,016
Trademarks	96	97
Other	8	8
Patents and other intangible assets	1,154	1,121
Accumulated amortization	(352)	(322)
Finite-Lived Intangible Assets, Net	802	799
Patents Pending
Patents	473	439
Issued Patents
Patents	577	577
Trademarks Pending
Trademarks	1	3
Registered Trademarks
Trademarks	$ 95	$ 94

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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Gross carrying amount before accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

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Gross carrying amount before accumulated amortization as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a specified period of time.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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