The Merger (Narrative) (Details) - USD ($)	May 09, 2019	Dec. 31, 2020	Dec. 31, 2019
Goodwill		$ 3,490,000	$ 3,490,000
AmpliPhi Biosciences Corporation [Member]
Purchase price			10,710,000
Goodwill			3,490,000
Deferred tax liability acquired			$ 3,077,000
Business combination, acquisition related costs	$ 1,100,000

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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