Stock Warrants - Summary of all warrant activity (Details) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Stock-Based Compensation
Number of Warrants, Beginning Balance	18,714,999	18,915,851
Number of Warrants, Granted	0
Number of Warrants, Exercised	0
Number of Warrants, Forfeited	0	(200,852)
Number of Warrants, Ending Balance	18,714,999	18,714,999
Weighted Average Exercise Price, Beginning Balance	$ 3.24	$ 3.85
Weighted Average Exercise Price, Granted	0
Weighted Average Exercise Price, Exercised	0
Weighted Average Exercise Price, Forfeited	0	61.25
Weighted Average Exercise Price, Ending Balance	$ 3.24	$ 3.24

Number of share warrants exercised during the period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans are exercise in period.

+ References

No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ 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
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Name Accounting Standards Codification
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-SubTopic 10
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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