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Note 15 - Long-Term Incentive Compensation (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Mutual Fund Awards [Member]
Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other than Options Value of Grants in Period	$ 142.8
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Deferred Incentive Plan [Member] | Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Deferred Incentive Plan [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	4 years

X

- Definition

The total dollar value of grants made during the period on other than stock options.

+ References

No definition available.

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X

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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

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