Basis of Presentation (Policies)	9 Months Ended
Sep. 30, 2020
Basis of Presentation
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements include the accounts of Merchants Bancorp, a registered bank holding company (the “Company”) and its wholly owned subsidiaries, Merchants Bank of Indiana (“Merchants Bank”) and Farmers-Merchants Bank of Illinois (“FMBI”). Merchants Bank’s direct and indirect subsidiaries include Merchants Capital Corp. (“MCC”), Merchants Capital Servicing, LLC (“MCS”), Ash Realty Holdings, LLC (“Ash Realty”), MBI Midtown West, LLC (“MMW”), Natty Mac Funding, Inc. (“NMF”), which became dormant in the first quarter of 2019 after the Company’s acquisition of the assets of NattyMac, LLC (“NattyMac”), and OneTrust Funding, Inc. In August 2019 the Company formed PR Mortgage Investment, LP (“PRMI”), PRMIGP, LLC (“PRMIGP”), and PR Mortgage Investment Management, LLC (“PRMIM”). In August 2020 the Company also formed Merchants Capital Investments, LLC (“MCI”) and Merchants Capital Tax Credit Equity Fund I, LP (“MCTCE-I”). All these entities are collectively referred to as the “Company”. The accompanying unaudited condensed consolidated balance sheet of the Company as of December 31, 2019, which has been derived from audited financial statements, and unaudited condensed consolidated financial statements of the Company as of September 30, 2020 and for the three and nine months ended September 30, 2020 and 2019, were prepared in accordance with the instructions for Form 10-Q and Article 10 of Regulation S-X and, therefore, do not include information or footnotes necessary for a complete presentation of financial position, results of operations and cash flows in conformity with accounting principles generally accepted in the United States of America. Accordingly, these condensed financial statements should be read in conjunction with the audited financial statements and notes thereto of the Company as of and for the year ended December 31, 2019 in its Annual Report on Form 10-K. Reference is made to the accounting policies of the Company described in the Notes to the Financial Statements contained in the Annual Report on Form 10-K. In the opinion of management, all adjustments (consisting only of normal recurring adjustments) which are necessary for a fair presentation of the unaudited financial statements have been included to present fairly the financial position as of September 30, 2020 and the results of operations for the three and nine months ended September 30, 2020 and 2019 and cash flows for the nine months ended September 30, 2020 and 2019. All interim amounts have not been audited and the results of operations for the three and nine months ended September 30, 2020, herein are not necessarily indicative of the results of operations to be expected for the entire year.
Principles of Consolidation	Principles of Consolidation The unaudited condensed consolidated financial statements as of and for the period ended September 30, 2020 and 2019 include results from the Company, and its wholly owned subsidiaries, Merchants Bank, and FMBI. Also included are Merchants Bank’s wholly owned subsidiaries, MCC, MCC’s wholly owned subsidiary, MCS, Ash Realty, NMF, MMW, and OneTrust Funding, Inc. The unaudited condensed consolidated financial statements as of and for the period ended September 30, 2020 also include PRMIGP and PRMIM, which are both 99% owned by Merchants Bank, and PRMI, which PRIMGP is the general partner of and Merchants Bank owns 50.4% of the total equity, as well as MCI owned 100% by MCC and its subsidiary MCTCE-I. All significant intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates 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 disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Reclassifications	Reclassifications Certain reclassifications have been made to the 2019 financial statements to conform to the financial statement presentation as of and for the three and nine months ended September 30, 2020. These reclassifications had no effect on net income.

Disclosure of accounting policy for basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

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