Note 4 - Mortgage Note Receivable - Scheduled Debt Principal Collections on Mortgage Note Receivable (Details) - USD ($)	Dec. 31, 2019	Jan. 21, 2016
2020	$ 39,061
2021	40,754
2022	42,520
2023	7,322
	$ 129,657	$ 265,000

Amount of long-term debt maturities principal collections on mortgage in next rolling year two.

No definition available.

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Period Type:	instant

- Definition

Amount of long-term debt maturities principal collections on mortgage in next rolling year four.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt maturities principal collections on mortgage in next rolling year three.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctdh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of long-term debt maturities principal collections on mortgage in next rolling twelve months.

+ References

No definition available.

+ Details

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Namespace Prefix:	ctdh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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Period Type:	instant