Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - shares	Jun. 30, 2021	Dec. 31, 2020
Limited partner's equity, units authorized (in shares)	8,000,000	8,000,000
Limited partner's equity, units issued (in shares)	5,334,473	5,441,928
Limited partner's equity, units outstanding (in shares)	5,334,473	5,441,928

The number of limited partner units authorized to be issued.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant