Note 19 - Related Party Transactions (Details Textual) $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($)
Cash Contribution Committed to Charitable Foundation	$ 1.5

Cash Contribution Committed to Charitable Foundation

No definition available.

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