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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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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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