Note 5 - Variable Interest Entities (Details Textual)	3 Months Ended
Mar. 31, 2023
Rubicon LLC [Member]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	50.00%
Arabian Amines Company [Member]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	50.00%

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-5A

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration