Stock-Based Compensation (Stock Option Valuation Assumptions) (Details)	12 Months Ended
Dec. 31, 2018 $ / shares	Dec. 31, 2017
AmpliPhi Biosciences Corporation [Member]
Expected volatility, minimum		117.00%
Common stock closing price	$ 0.21
AmpliPhi Biosciences Corporation [Member] \| Restricted Stock [Member]
Risk-free interest rate, maximum	2.99%	2.36%
Risk-free interest rate, minimum	2.74%	1.27%
Expected volatility, maximum	126.00%	144.00%
Expected volatility, minimum	121.00%
Expected term (in years)	6 years 7 days
Expected dividend yield	0.00%	0.00%
Measurement Input, Expected Dividend Rate [Member] \| C3J [Member]
Equity Securities, FV-NI, Measurement Input		0
Measurement Input, Expected Term [Member] \| C3J [Member]
Equity Securities, FV-NI, Measurement Input		6.25
Measurement Input, Price Volatility [Member] \| C3J [Member]
Equity Securities, FV-NI, Measurement Input		106
Measurement Input, Risk Free Interest Rate [Member] \| C3J [Member]
Equity Securities, FV-NI, Measurement Input		1.97
Minimum [Member] \| AmpliPhi Biosciences Corporation [Member] \| Restricted Stock [Member]
Expected term (in years)		2 years
Maximum [Member] \| AmpliPhi Biosciences Corporation [Member] \| Restricted Stock [Member]
Expected term (in years)		9 years 1 month 6 days

Value of input used to measure investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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