Income taxes (Details - Income taxes paid net of refunds) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Effective Income Tax Rate Reconciliation [Line Items]
Income taxes paid	$ 5,588	$ 5,987
ILLINOIS
Effective Income Tax Rate Reconciliation [Line Items]
Income taxes paid	1,087	1,134
CALIFORNIA
Effective Income Tax Rate Reconciliation [Line Items]
Income taxes paid	0	338
Other Country [Member]
Effective Income Tax Rate Reconciliation [Line Items]
Income taxes paid	655	364
Federal [Member]
Effective Income Tax Rate Reconciliation [Line Items]
Income taxes paid	$ 3,846	$ 4,151

Amount, before refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-2A

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-23

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-22

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147482740/230-10-45-25

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-2

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