Stock-Based Compensation - Schedule of Warrants Outstanding and Exercisable (Details) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Warrants Outstanding, Number of Warrants	20,737,500	18,702,500
Warrants Exercisable, Weighted Average Remaining Life In Years	1 year 18 days	2 years 6 months
Warrants Weighted- Average Exercise Price	$ 0.20	$ 0.20
Warrants Exercisable, Exercisable Number of Warrants	20,737,500	15,237,500
Exercise Price One [Member] \| Warrants [Member]
Warrants Outstanding, Exercise Price	$ 0.20	$ 0.20
Warrants Outstanding, Number of Warrants	1,487,500	1,487,500
Warrants Exercisable, Weighted Average Remaining Life In Years	2 years 29 days	2 years 6 months
Warrants Weighted- Average Exercise Price	$ 0.20	$ 0.20
Warrants Exercisable, Exercisable Number of Warrants	1,487,500	1,487,500
Exercise Price Two [Member] \| Warrants [Member]
Warrants Outstanding, Exercise Price	$ 0.20	$ 0.20
Warrants Outstanding, Number of Warrants	19,250,000	3,465,000
Warrants Exercisable, Weighted Average Remaining Life In Years	2 years 1 month 24 days
Warrants Weighted- Average Exercise Price	$ 0.20	$ 0.20
Warrants Exercisable, Exercisable Number of Warrants	19,250,000

Warrants weighted- average exercise price of warrants.

No definition available.

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Namespace Prefix:	OTLC_
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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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- Details

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- Details

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