Name:	mdu_MaximumLengthOfTimeAllowedToHedgeCashFlowHedgeSales
Namespace Prefix:	mdu_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted purchase transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

No definition available.

Name:	mdu_MaximumLengthOfTimeAllowedToHedgeInCashFlowHedgePurchase
Namespace Prefix:	mdu_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

Maximum length of time over which the entity is hedging its exposure to foreign currency.

No definition available.

Name:	mdu_MaximumLengthOfTimeAllowedToHedgeInForeignCurrencyCashFlowHedge
Namespace Prefix:	mdu_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

No definition available.

Name:	mdu_MaximumLengthOfTimeAllowedToHedgeInInterestRateCashFlowHedge
Namespace Prefix:	mdu_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

Maximum length of time for the settlement of all interest rate derivative transactions.

No definition available.

Name:	mdu_MaximumPeriodForSettlementOfAllInterestRateDerivativeTransactions
Namespace Prefix:	mdu_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

Maximum length of time for the settlement of foreign currency derivative transactions.

No definition available.