Bond Receivable, Amount in Exchange of Land Development Improvement

No definition available.

Name:	mdc_BondReceivableAmountInExchangeOfLandDevelopmentImprovement
Namespace Prefix:	mdc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Cash Contribution Committed to Charitable Foundation

+ References

No definition available.

+ Details

Name:	mdc_CashContributionCommittedToCharitableFoundation
Namespace Prefix:	mdc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the yearly rental rate per rentable square foot under an operating lease.

+ References

No definition available.

+ Details

Name:	mdc_OperatingLeasesYearlyRentalRatePerRentableSquareFoot
Namespace Prefix:	mdc_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

+ Details

Name:	us-gaap_InvestmentIncomeInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cost of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

+ Details

Name:	us-gaap_InvestmentOwnedAtCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=mdc_CVenturesIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=mdc_DistrictMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=mdc_CapitalAppreciationBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=mdc_SubordinateBondMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 16 - Related Party Transactions (Details Textual) $ in Thousands					12 Months Ended
	Oct. 31, 2026	Nov. 01, 2021	Oct. 31, 2021	Nov. 01, 2016 ft²	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)
Cash Contribution Committed to Charitable Foundation					$ 1,000	$ 1,000	$ 3,000
CVentures, Inc. [Member]
Area of Real Estate Property \| ft²				5,437
Operating Leases, Yearly Rental Rate Per Rentable Square Foot				26.50
CVentures, Inc. [Member] \| Forecast [Member]
Operating Leases, Yearly Rental Rate Per Rentable Square Foot	31.67	29.26	28.68
District [Member]
Bond Receivable, Amount in Exchange of Land Development Improvement								$ 28,600
Investment Income, Interest					$ 0	$ 0	$ 1,700
District [Member] \| Capital Appreciation Bonds [Member]
Investment Owned, at Cost								22,500
District [Member] \| Subordinate Bond [Member]
Investment Owned, at Cost								$ 1,600