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v3.23.2

Cover page - shares | 6 Months Ended |
--- | --- | ---
Jun. 30, 2023 | Aug. 01, 2023
Document Information [Line Items] |  |
Document Type | 10-Q |
Document Quarterly Report | true |
Document Period End Date | Jun. 30, 2023 |
Document Transition Report | false |
Entity File Number | 1-03480 |
Entity Registrant Name | MDU RESOURCES GROUP INC |
Entity Incorporation, State or Country Code | DE |
Entity Tax Identification Number | 30-1133956 |
Entity Address, Address Line One | 1200 West Century Avenue |
Entity Address, Address Line Two | P.O. Box 5650 |
Entity Address, City or Town | Bismarck |
Entity Address, State or Province | ND |
Entity Address, Postal Zip Code | 58506-5650 |
City Area Code | 701 |
Local Phone Number | 530-1000 |
Title of 12(b) Security | Common Stock, par value $1.00 per share |
Trading Symbol | MDU |
Security Exchange Name | NYSE |
Entity Current Reporting Status | Yes |
Entity Interactive Data Current | Yes |
Entity Filer Category | Large Accelerated Filer |
Entity Small Business | false |
Entity Emerging Growth Company | false |
Entity Shell Company | false |
Entity common stock, shares outstanding |  | 203,638,373
Entity Central Index Key | 0000067716 |
Current Fiscal Year End Date | --12-31 |
Document Fiscal Year Focus | 2023 |
Document Fiscal Period Focus | Q2 |
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