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Stockholders' Equity - Preferred Stock (Details) - $ / shares	1 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Preferred Stock [Abstract]
Preferred stock, shares authorized (in shares)		5,000,000	5,000,000
Preferred stock, par value (in dollars per share)		$ 0.001	$ 0.001
Preferred stock, shares outstanding (in shares)		1,954	1,959
Series A Convertible Preferred Stock [Member]
Preferred Stock [Abstract]
Preferred stock, shares outstanding (in shares)		0	0
Convertible preferred stock		3.60%	3.60%
Series B Convertible Preferred Stock [Member]
Preferred Stock [Abstract]
Preferred stock, shares outstanding (in shares)		1,016	1,021
Series B Convertible Preferred Stock [Member] | 2018 Rights Offering [Member]
Preferred Stock [Abstract]
Preferred stock, shares outstanding (in shares)		1,016
Number of preferred stock, shares converted		6,096
Series C Convertible Preferred Stock [Member]
Preferred Stock [Abstract]
Preferred stock, shares outstanding (in shares)		938	938
Conversion Price Per Share	$ 3.2132
Preferred stock conversion price reduced (in dollars per share)	$ 2.25
Series C Convertible Preferred Stock [Member] | 2018 Rights Offering [Member]
Preferred Stock [Abstract]
Preferred stock, shares outstanding (in shares)		938
Number of preferred stock, shares converted		416,889

X

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Conversion price per share.

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Number Of Preferred Stock Shares Exercised.

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Preferred Stock [Abstract]

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- Definition

Per share decrease in conversion price of convertible preferred stock. Excludes change due to standard antidilution provision.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

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The percentage rate used to calculate dividend payments on preferred stock.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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