Ratio of total debt to total capitalization as specified in debt covenants

No definition available.

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Namespace Prefix:	mdu_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-15

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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Subsequent Events (Details 1) - USD ($) $ in Thousands		3 Months Ended
Subsequent Events (Details 1) - USD ($) $ in Thousands	Apr. 21, 2023	Mar. 31, 2023	Mar. 31, 2022	May 01, 2023	Jan. 20, 2023	Dec. 31, 2022
Short-Term Debt [Line Items]
Repayment of short-term borrowings		$ 20,000	$ 0
Short-term borrowings		501,500	$ 99,958			$ 246,500
Term Loan Agreement \| Intermountain Gas Company
Short-Term Debt [Line Items]
Repayment of short-term borrowings		$ 20,000
Short-term borrowings					$ 125,000
Ratio of total debt to total capitalization as specified in debt covenants					65.00%
Term Loan Agreement \| Subsequent Event [Member] \| Intermountain Gas Company
Short-Term Debt [Line Items]
Repayment of short-term borrowings	$ 30,000
Term Loan Agreement \| Subsequent Event [Member] \| MDU Resources Group [Member]
Short-Term Debt [Line Items]
Short-term borrowings				$ 75,000
Ratio of total debt to total capitalization as specified in debt covenants				65.00%