Stock-Based Compensation (Details - Future Stock Option Plans) shares in Thousands	Dec. 31, 2023 shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)	144
Plan 2021 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)	113
Plan 2015 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)	27
Plan 2005 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)	4

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.

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+ Details