General information.

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Number of additional patents in process.

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Number of patents granted.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of lessee's right to use underlying asset under operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
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General Information - Additional Information (Details) $ in Thousands	Mar. 31, 2020 USD ($) Patent	Dec. 31, 2019 USD ($)	Jul. 01, 2019 USD ($)
General Information [Line Items]
Number of patents granted \| Patent	37
Number of additional patents in process \| Patent	5
ROU asset	$ 937
Lease obligation	$ 985
ASU 2016-02
General Information [Line Items]
ROU asset		$ 414	$ 1,600
Lease obligation		$ 414	1,600
Cumulative impact of change in accounting policy			$ 230