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v3.23.3

Operations and Significant Accounting Policies - Other Non-Current Liabilities (Details) - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Business Segments [Line Items] |  |
Asset Retirement Obligation | $ 200.8 | $ 200.4
PSAs | 22.4 | 26.9
Operating Lease Liabilities | 8.5 | 9.3
Finance Lease Liabilities | 1.7 | 0.0
Other | 30.4 | 32.4
Other Non-Current Liabilities | 263.8 | 269.0
BNI Energy |  |
Business Segments [Line Items] |  |
Other Receivables | $ 32.4 | $ 32.4

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