v3.21.1

Loans Receivable and the Allowance for Credit Losses - Primary Type of Collateral (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	$ 3,307,511	$ 3,426,723
Financing receivable, allowance for credit loss	50,650	55,500	$ 51,187	$ 29,079
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	33,233	29,845
Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	3,132	3,869
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	3,338	3,626
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	39,703	37,340
Financing receivable, allowance for credit loss	3,468	3,075
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	1,110	1,346	1,146	3,748
Agricultural | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	963	516
Agricultural | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	758	824
Agricultural | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	742	748
Agricultural | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	2,463	2,088
Financing receivable, allowance for credit loss	39	66
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	13,644	15,689	19,309	8,394
Commercial and industrial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	629	667
Commercial and industrial | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	2,366	3,037
Commercial and industrial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	2,596	2,878
Commercial and industrial | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	5,591	6,582
Financing receivable, allowance for credit loss	773	799
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	30,425	32,640	23,138	13,804
Commercial real estate | Construction & development | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	595	899
Commercial real estate | Construction & development | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Construction & development | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Construction & development | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	595	899
Financing receivable, allowance for credit loss	0	0
Commercial real estate | Farmland | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	10,132	7,850
Commercial real estate | Farmland | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Farmland | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Farmland | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	10,132	7,850
Financing receivable, allowance for credit loss	123	88
Commercial real estate | Multifamily | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	1,096	746
Commercial real estate | Multifamily | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Multifamily | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Multifamily | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	1,096	746
Financing receivable, allowance for credit loss	452	202
Commercial real estate | Commercial real estate-other | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	19,126	18,740
Commercial real estate | Commercial real estate-other | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Commercial real estate-other | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Commercial real estate | Commercial real estate-other | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	19,126	18,740
Financing receivable, allowance for credit loss	1,911	1,741
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	4,655	4,882	6,425	2,685
Residential real estate | One- to four- family first liens | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	483	204
Residential real estate | One- to four- family first liens | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Residential real estate | One- to four- family first liens | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Residential real estate | One- to four- family first liens | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	483	204
Financing receivable, allowance for credit loss	132	132
Residential real estate | One- to four- family junior liens | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	209	223
Residential real estate | One- to four- family junior liens | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Residential real estate | One- to four- family junior liens | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Residential real estate | One- to four- family junior liens | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	209	223
Financing receivable, allowance for credit loss	38	47
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	816	943	$ 1,169	$ 448
Consumer | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Consumer | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	8	8
Consumer | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	0	0
Consumer | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	8	8
Financing receivable, allowance for credit loss	$ 0	$ 0

X

- 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

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

+ Details

Name:	us-gaap_NotesReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_CollateralAxis=us-gaap_RealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CollateralAxis=us-gaap_EquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CollateralAxis=mofg_OtherCollateralNotSeparatelyDisclosedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=mofg_AgriculturalPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_ConstructionAndDevelopmentLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_FarmlandLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_MultifamilyRealEstateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_CommercialRealEstateOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_FirstLienLoanFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mofg_JuniorLienLoanFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: