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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

+ Details

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Subparagraph (e)(1)
-Name Accounting Standards Codification
-Paragraph 2
-Section 50
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Share based compensation (Details 1) - $ / shares	12 Months Ended
Share based compensation (Details 1) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Number Of Stock Options Exercisable	877,820	461,320	358,660
Average Remaining Contractual Life (years)	3 years 10 months 24 days
Exercise Price	$ 0.25	$ 0.51	$ 0.56	$ 0.83
Number Of Stock Options Outstanding	2,927,820	461,320	358,660	421,000
Options 8
Number Of Stock Options Exercisable	21,360
Average Remaining Contractual Life (years)	2 years 6 months
Exercise Price	$ 0.440
Number Of Stock Options Outstanding	21,360
Options 1
Number Of Stock Options Exercisable	69,200
Average Remaining Contractual Life (years)	3 years 10 months 24 days
Exercise Price	$ 0.174
Number Of Stock Options Outstanding	69,200
Options 2
Number Of Stock Options Exercisable	166,200
Average Remaining Contractual Life (years)	4 years 4 months 24 days
Exercise Price	$ 0.200
Number Of Stock Options Outstanding	166,200
Options 3
Number Of Stock Options Exercisable	55,200
Average Remaining Contractual Life (years)	4 years
Exercise Price	$ 0.216
Number Of Stock Options Outstanding	2,005,200
Options 4
Number Of Stock Options Exercisable	115,250
Average Remaining Contractual Life (years)	4 years 8 months 12 days
Exercise Price	$ 0.252
Number Of Stock Options Outstanding	115,250
Options 5
Average Remaining Contractual Life (years)	4 years 8 months 12 days
Exercise Price	$ 0.259
Number Of Stock Options Outstanding	100,000
Options 6
Number Of Stock Options Exercisable	52,650
Average Remaining Contractual Life (years)	4 years
Exercise Price	$ 0.260
Number Of Stock Options Outstanding	52,650
Options 7
Number Of Stock Options Exercisable	177,200
Average Remaining Contractual Life (years)	4 years
Exercise Price	$ 0.264
Number Of Stock Options Outstanding	177,200
Options 9
Number Of Stock Options Exercisable	16,000
Average Remaining Contractual Life (years)	1 year 9 months 18 days
Exercise Price	$ 0.510
Number Of Stock Options Outstanding	16,000
Options 10
Number Of Stock Options Exercisable	100,000
Average Remaining Contractual Life (years)	6 months
Exercise Price	$ 0.520
Number Of Stock Options Outstanding	100,000
Options 11
Number Of Stock Options Exercisable	30,000
Average Remaining Contractual Life (years)	1 year 1 month 6 days
Exercise Price	$ 0.550
Number Of Stock Options Outstanding	30,000
Options 12
Number Of Stock Options Exercisable	18,050
Average Remaining Contractual Life (years)	3 years
Exercise Price	$ 0.620
Number Of Stock Options Outstanding	18,050
Options 13
Number Of Stock Options Exercisable	32,250
Average Remaining Contractual Life (years)	3 years 2 months 12 days
Exercise Price	$ 0.680
Number Of Stock Options Outstanding	32,250
Options 14
Number Of Stock Options Exercisable	24,460
Average Remaining Contractual Life (years)	3 years 4 months 24 days
Exercise Price	$ 0.720
Number Of Stock Options Outstanding	24,460