1. Summary of Significant Accounting Policies (Details - Stock purchases) - Common Stock [Member] - $ / shares	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Total stock purchases	378,470	838,497
Average price for total stock purchases	$ 3.97	$ 3.87
Open Market Purchases [Member]
Total stock purchases	335,546	714,898
Average price for total stock purchases	$ 3.95	$ 3.81
Shares redeemed upon net exercise of stock options
Total stock purchases	18,424	33,599
Average price for total stock purchases	$ 3.76	$ 4.37
Other Purchases [Member]
Total stock purchases	24,500	90,000
Average price for total stock purchases	$ 4.20	$ 4.13

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

Reference 1: 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 2: 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=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration