Consolidated Statements of Changes in Stockholders' Equity (Deficit) (Parenthetical) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement Of Stockholders Equity [Abstract]
At the market offering, issuance costs	$ 17,000	$ 800,000
Public offering issuance costs	$ 2,600,000

Issuance of common stock from at the market offering, issuance costs.

No definition available.

Name:	htgm_IssuanceOfCommonStockFromAtTheMarketOfferingIssuanceCosts
Namespace Prefix:	htgm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration