Fair Value of Financial Assets and Liabilities (Fair Value of Financial Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3	0	0
Total assets	4,282,000	9,430,000
Asset acquisition derivative liability		1,117,000
Total liabilities		1,117,000
C3J [Member]
Total assets		9,430,000	$ 13,983,000
Asset acquisition derivative liability		1,117,000
Total liabilities		1,117,000
Money Market Funds [Member]
Cash and Cash equivalents	4,282,000	9,430,000
Money Market Funds [Member] \| C3J [Member]
Cash and Cash equivalents		9,430,000	4,332,000
Fair Value, Inputs, Level 1 [Member]
Total assets	4,282,000	9,430,000
Fair Value, Inputs, Level 1 [Member] \| C3J [Member]
Total assets		9,430,000	4,332,000
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Cash and Cash equivalents	$ 4,282,000	9,430,000
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member] \| C3J [Member]
Cash and Cash equivalents		9,430,000	4,332,000
Fair Value, Inputs, Level 2 [Member] \| C3J [Member]
Total assets			9,651,000
Fair Value, Inputs, Level 3 [Member]
Asset acquisition derivative liability		1,117,000
Total liabilities		1,117,000
Fair Value, Inputs, Level 3 [Member] \| C3J [Member]
Asset acquisition derivative liability		1,117,000
Total liabilities		$ 1,117,000
Corporate Debt Securities [Member] \| C3J [Member]
Cash and Cash equivalents			9,651,000
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| C3J [Member]
Cash and Cash equivalents			$ 9,651,000

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

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Fair value of financial and nonfinancial obligations.

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