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v3.23.2

Long-term debt outstanding (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2022 | May 31, 2023 | Dec. 31, 2022
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 2,247,422 | $ 2,247,422 | $ 2,090,200 |  | $ 2,365,667
Long-term debt due within one year | 1,319 | 1,319 | 86,319 |  | 47,819
Long-term debt | 2,246,103 | 2,246,103 | 2,003,881 |  | 2,317,848
Repayments of Long-term Debt |  | 506,191 | 147,397 |  |
Senior Notes |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 1,757,000 | $ 1,757,000 | 1,847,000 |  | 1,848,500
Weighted Average Interest Rate | 4.33% | 4.33% |  |  |
Term Loan Agreements |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 382,000 | $ 382,000 | 7,700 |  | 7,000
Weighted Average Interest Rate | 6.46% | 6.46% |  |  |
Commercial Paper |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 58,900 | $ 58,900 | 175,020 |  | 349,050
Weighted Average Interest Rate | 5.70% | 5.70% |  |  |
Medium-term Notes |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 35,000 | $ 35,000 | 35,000 |  | 35,000
Weighted Average Interest Rate | 7.32% | 7.32% |  |  |
Credit Agreements |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 20,300 | $ 20,300 | 29,860 |  | 130,000
Weighted Average Interest Rate | 8.35% | 8.35% |  |  |
Other Notes |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt | $ 987 | $ 987 | 1,621 |  | 1,614
Weighted Average Interest Rate | 2.24% | 2.24% |  |  |
Long-term Debt |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Unamortized Debt Issuance Costs | $ 6,765 | $ 6,765 | 5,406 |  | 5,211
Discount | 0 | $ 0 | $ 595 |  | $ 286
Long-term Debt | Centennial Energy Holdings, Inc. |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Repayments of Long-term Debt | $ 455,000 |  |  |  |
Revolving Credit Facility | MDU Resources Group, Inc. |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt |  |  |  | $ 200,000 |
Ratio of total debt to total capitalization as specified in debt covenants |  |  |  | 65.00% |
Term Loan Agreement | MDU Resources Group, Inc. |  |  |  |  |
Long-term debt outstanding [Line Items] |  |  |  |  |
Long-term debt |  |  |  | $ 375,000 |
Ratio of total debt to total capitalization as specified in debt covenants |  |  |  | 65.00% |

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