The net cash inflow from the additional capital contribution to the entity after payment for issuance costs.

No definition available.

Name:	thmo_ProceedsFromIssuanceOfCommonStockNet
Namespace Prefix:	thmo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Average per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	thmo_SharesIssuedAveragePricePerShare
Namespace Prefix:	thmo_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsOfStockIssuanceCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=thmo_ImmunecyteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=thmo_AtTheMarketOfferingAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 15 - Subsequent Events (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
Note 15 - Subsequent Events (Details Textual) - USD ($)	Mar. 17, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 16, 2021	Sep. 30, 2020	Nov. 26, 2019
Proceeds from Issuance of Common Stock, Net		$ 10,839,000	$ 756,000
ImmuneCyte [Member]
Equity Method Investment, Ownership Percentage		18.79%			18.79%	20.00%
Subsequent Event [Member] \| ImmuneCyte [Member]
Equity Method Investment, Ownership Percentage	8.80%			18.79%
At The Market Offering Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		2,620,652
Proceeds from Issuance of Common Stock		$ 8,224,000
Shares Issued, Average Price Per Share (in dollars per share)		$ 3.14
Proceeds from Issuance of Common Stock, Net		$ 7,731,000
Payments of Stock Issuance Costs		$ 493,000
At The Market Offering Agreement [Member] \| Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)	2,976,832
Proceeds from Issuance of Common Stock	$ 7,056,000
Shares Issued, Average Price Per Share (in dollars per share)	$ 2.37
Proceeds from Issuance of Common Stock, Net	$ 6,832,000
Payments of Stock Issuance Costs	$ 224,000