(1) Summary of Significant Accounting Policies (Details - Options outstanding and exercisable) - shares shares in Thousands	Mar. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	15,834	15,977
Number of shares, exercisable	12,499	12,597
$0.95 - $1.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	1,878	1,904
Number of shares, exercisable	1,878	1,904
$2.00 - $2.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	1,570	1,570
Number of shares, exercisable	180	180
$3.00 - $3.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	4,863	4,973
Number of shares, exercisable	3,234	3,306
$4.00 - $4.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	1,533	1,540
Number of shares, exercisable	1,217	1,217
$5.00 - $5.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	0	0
Number of shares, exercisable	0	0
$6.00 - $6.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	4,770	4,770
Number of shares, exercisable	4,770	4,770
$7.00 - $7.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of shares, outstanding	1,220	1,220
Number of shares, exercisable	1,220	1,220

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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