Note 8 - Commitments and Contingencies (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2021	Jul. 13, 2020
Short Term Investment Minimum		$ 1,000,000
Minimum [Member]
Period Of Warranty On Products (Year)	1 year
Maximum [Member]
Period Of Warranty On Products (Year)	2 years

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios, and adherence to certain clauses which must be met in order to avoid default. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

No definition available.

Name:	thmo_ShortTermInvestmentMinimum
Namespace Prefix:	thmo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant