Exercise price per share or per unit of warrants or rights outstanding.

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=123467817&loc=d3e21475-112644

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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- Definition

Class of Warrant or Right, Expired

+ References

No definition available.

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Stockholders' Equity - Common Stock Warrants (Details) - Common Stock - $ / shares	Jun. 30, 2021	May 03, 2021	Apr. 28, 2021	Mar. 27, 2021	Dec. 31, 2020
Class of Warrant or Right [Line Items]
Number of shares called by warrants (in shares)	0				413,320
Exercise price (in dollars per share)					$ 3.00
Warrant expirations (in shares)		117,262	132,884	163,174