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Note 16 - Unit-based Compensation (Details Textual) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2017
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)		1,600,000			800,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	800,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value		$ 6.7	$ 16.0	$ 7.9
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 9.5	13.3
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 6 months
Payment, Tax Withholding, Share-Based Payment Arrangement		$ 6.4	3.2	2.9
General and Administrative Expenses and Operating and Maintenance Expense [Member]
Share-Based Payment Arrangement, Expense		11.3	10.9	$ 5.8
Market-based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value		$ 2.5	$ 2.8
Director [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		1 year

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The fair value of grants made during the period on other than stock option plans.

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-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

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