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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-SubTopic 10
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Related Party Transactions - Additional Information (Details) - USD ($)		1 Months Ended					3 Months Ended		9 Months Ended
	Oct. 01, 2019	Sep. 30, 2020	Aug. 31, 2020	Jul. 31, 2020	Jun. 30, 2020	May 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jan. 02, 2021	Dec. 31, 2019
Related Party Transaction [Line Items]
Common stock, shares issued		19,590,998					19,590,998		19,590,998			12,344,818
Related party transaction, other									$ 0	$ 0
EVERSANA \| Leana Wood
Related Party Transaction [Line Items]
Related party certain marketing cost							$ 300,000	$ 200,000	900,000	200,000
DermTech Operations \| Scenario Forecast
Related Party Transaction [Line Items]
Common stock, shares issued											5,000
DermTech Operations \| Michael Dobak
Related Party Transaction [Line Items]
Related party certain marketing cost		$ 15,000	$ 15,000	$ 15,000	$ 15,000	$ 15,000	$ 45,000	$ 0	$ 100,000	$ 0
DermTech Operations \| Michael Dobak \| Maximum
Related Party Transaction [Line Items]
Related party certain marketing cost	$ 100,000