Basis of Presentation	3 Months Ended
Mar. 31, 2013
Basis of Presentation [Abstract]
Basis of Accounting [Text Block]	Basis of Presentation The accompanying Unaudited Condensed Consolidated Financial Statements (the “financial statements”) of M/I Homes, Inc. and its subsidiaries (the “Company”) and notes thereto have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial information. The financial statements include the accounts of M/I Homes, Inc. and its subsidiaries. All intercompany transactions have been eliminated. Results for the interim period are not necessarily indicative of results for a full year. In the opinion of management, the accompanying financial statements reflect all adjustments (all of which are normal and recurring in nature) necessary for a fair presentation of financial results for the interim periods presented. These financial statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2012 (the “2012 Form 10-K”). The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during that period. Actual results could differ from these estimates and have a significant impact on the financial condition and results of operations and cash flows. With regard to the Company, estimates and assumptions are inherent in calculations relating to valuation of inventory and investment in unconsolidated limited liability companies (“Unconsolidated LLCs”), property and equipment depreciation, valuation of derivative financial instruments, accounts payable on inventory, accruals for costs to complete inventory, accruals for warranty claims, accruals for self-insured general liability claims, litigation, accruals for health care and workers' compensation, accruals for guaranteed or indemnified loans, stock-based compensation expense, income taxes, and contingencies. Items that could have a significant impact on these estimates and assumptions include the risks and uncertainties listed in “Item 1A. Risk Factors” in Part I of our 2012 Form 10-K, as the same may be updated from time to time in our subsequent filings with the SEC. Impact of New Accounting Standards In January 2013, the FASB issued ASU No. 2013-01: Balance Sheet (Topic 210) - Disclosures about Offsetting Assets and Liabilities (“ASU 2013-01”). ASU 2013-01 amended ASU 2011-11 and will enhance disclosures required by U.S. GAAP by requiring additional information about financial and derivative instruments that are either (1) offset in accordance with Section 210-20-45 or Section 815-10-45 or (2) subject to an enforceable master netting arrangement or similar agreement, irrespective of whether they are offset in accordance with Section 210-20-45 or Section 815-10-45. We are required to apply the amendments for annual reporting periods beginning on or after January 1, 2013, and for interim periods within those annual periods. The Company adopted this standard on January 1, 2013 and the adoption did not have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements.

Basis of Presentation

The accompanying Unaudited Condensed Consolidated Financial Statements (the “financial statements”) of M/I Homes, Inc. and its subsidiaries (the “Company”) and notes thereto have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial information. The financial statements include the accounts of M/I Homes, Inc. and its subsidiaries. All intercompany transactions have been eliminated. Results for the interim period are not necessarily indicative of results for a full year. In the opinion of management, the accompanying financial statements reflect all adjustments (all of which are normal and recurring in nature) necessary for a fair presentation of financial results for the interim periods presented. These financial statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2012 (the “2012 Form 10-K”).

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during that period. Actual results could differ from these estimates and have a significant impact on the financial condition and results of operations and cash flows. With regard to the Company, estimates and assumptions are inherent in calculations relating to valuation of inventory and investment in unconsolidated limited liability companies (“Unconsolidated LLCs”), property and equipment depreciation, valuation of derivative financial instruments, accounts payable on inventory, accruals for costs to complete inventory, accruals for warranty claims, accruals for self-insured general liability claims, litigation, accruals for health care and workers' compensation, accruals for guaranteed or indemnified loans, stock-based compensation expense, income taxes, and contingencies. Items that could have a significant impact on these estimates and assumptions include the risks and uncertainties listed in “Item 1A. Risk Factors” in Part I of our 2012 Form 10-K, as the same may be updated from time to time in our subsequent filings with the SEC.

Impact of New Accounting Standards

In January 2013, the FASB issued ASU No. 2013-01: Balance Sheet (Topic 210) - Disclosures about Offsetting Assets and Liabilities (“ASU 2013-01”). ASU 2013-01 amended ASU 2011-11 and will enhance disclosures required by U.S. GAAP by requiring additional information about financial and derivative instruments that are either (1) offset in accordance with Section 210-20-45 or Section 815-10-45 or (2) subject to an enforceable master netting arrangement or similar agreement, irrespective of whether they are offset in accordance with Section 210-20-45 or Section 815-10-45. We are required to apply the amendments for annual reporting periods beginning on or after January 1, 2013, and for interim periods within those annual periods. The Company adopted this standard on January 1, 2013 and the adoption did not have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements.