Number of financing receivables that are in the process of foreclosure.

No definition available.

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Namespace Prefix:	mbin_
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Period Type:	duration

- Definition

The amount of residential loans in process of foreclosure.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

+ Details

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- Details

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Balance Type:
Period Type:

Loans and Allowance for Loan Losses - Troubled Debt and Modifications (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020 item	Jun. 30, 2019 item	Jun. 30, 2020 loan item	Jun. 30, 2019 item	Dec. 31, 2019 USD ($) loan
Troubled debt and modifications
Number of troubled debt restructuring	0	0	0	0
Number of loans restructured during the last twelve months that defaulted during the period	0	0	0	0
Residential real estate
Troubled debt and modifications
Number of loans in the process of foreclosure \| loan			0		1
Value of residential loans in process of foreclosure \| $					$ 725,000