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

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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 maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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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.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Stockholders' Equity (Details) - $ / shares	Jun. 04, 2018	Jun. 30, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Stock shares authorized (in shares)		300,000,000
Preferred stock, shares authorized (in shares)		100,000,000
Common stock, shares issued (in shares)		20,492,236
Common stock, shares outstanding (in shares)		20,318,014
Warrants exercise price (USD per share)		$ 0.001
Ownership percentage, individual		10.00%
Ownership percentage, investor		20.00%
Class A common stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)		100,000,000	100,000,000
Common stock, shares issued (in shares)		17,917,636	15,750,097
Common stock, shares outstanding (in shares)		17,743,414	15,681,439
Ownership percentage, individual		50.00%
Ownership percentage, investor		20.00%
Sale of stock price (usd per share)		$ 25.00
Class B Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)		100,000,000	100,000,000
Common stock, shares issued (in shares)		2,574,600	1,926,848
Common stock, shares outstanding (in shares)		2,574,600	1,926,848
Sale of stock price (usd per share)		$ 25.00
Series I Warrants
Class of Stock [Line Items]
Number of warrants issued (shares)	3,016,853
Warrants exercise price (USD per share)	$ 0.0000001
Sale of stock price (usd per share)		25.00
Series 2 warrants
Class of Stock [Line Items]
Number of warrants issued (shares)	712,736
Warrants exercise price (USD per share)	$ 0.0000001
Sale of stock price (usd per share)		$ 25.00