XML 72 R55.htm IDEA: XBRL DOCUMENT
v3.22.4

STOCKHOLDERS' EQUITY - PERFORMANCE BASED STOCK OPTIONS (Details) - shares | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Stock options granted (in shares) | 19,747,760 |
Performance-Based Stock Options |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Stock options granted (in shares) | 2,741,750 | 550,000

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Gross number of share options (or share units) granted during the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(01) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=gern_PerformanceBasedStockOptionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |