Debt MIF Warehousing Agreement (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]
Maximum Borrowing Availability under all Credit Lines	$ 125,000,000	$ 115,000,000
Notes payable bank - financial services operations	85,379,000	80,029,000
Warehousing Agreement - First Amendment to Amended and Restated [Member]
Line of Credit Facility [Line Items]
M/I Financial Maximum Borrowing Capacity	110,000,000
Optional increase in borrowing availability	20,000,000
Aggreate Maximum Principal Amount Permitted to be Outstanding Under All Warehousing Credit Lines	150,000,000
Minimum Net Worth Required for Compliance	11,000,000
Minimum required liquidity for compliance	5,500,000
LIBOR basis points	275
Debt Instrument, Basis Spread on Variable Rate	3.00%
Warehousing Agreement - Amended and Restated [Member]
Line of Credit Facility [Line Items]
Minimum Net Worth Required for Compliance	10,000,000
Minimum required liquidity for compliance	5,000,000
Repurchase Agreement [Member]
Line of Credit Facility [Line Items]
M/I Financial Maximum Borrowing Capacity	$ 15,000,000
Minimum [Member] | Repurchase Agreement [Member]
Line of Credit Facility [Line Items]
LIBOR basis points	275
Maximum [Member] | Repurchase Agreement [Member]
Line of Credit Facility [Line Items]
LIBOR basis points	300