Decrease in maximum borrowing capacity for debt instruments.

No definition available.

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- Definition

Long-term private shelf agreement.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Long-term private shelf agreement amended issuance capacity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Note purchase agreement.

+ References

No definition available.

+ Details

Name:	mdu_NotePurchaseAgreement
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Balance Type:	credit
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- Definition

Ratio - EBIT to interest expense.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Ratio - EBITDA to interest expense.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Ratio of funded debt capitalization - Company alone, as specified in debt convenants.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Ratio of funded debt to total capitalization as specified in debt convenants.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Ratio of subsidiary debt to subsidiary capitalization as specified in debt convenants.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Ratio of total debt to adjusted total capitalization as specified in debt convenants.

+ References

No definition available.

+ Details

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Namespace Prefix:	mdu_
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Period Type:	instant

- Definition

Ratio of total debt to total capitalization as specified in debt convenants.

+ References

No definition available.

+ Details

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Namespace Prefix:	mdu_
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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Details

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- Details

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- Details

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