Name:	ibcp_ContractDisclosureOffBalanceSheetRisksAmount
Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Refers to variable rate on standby letters of credit.

No definition available.

Name:	ibcp_ContractDisclosureOffBalanceSheetRisksLiabilityVariableRate
Namespace Prefix:	ibcp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Ratio applied to the conversion of one type or class of equity instrument into another type or class of equity instrument.

No definition available.

Name:	ibcp_EquityInvestmentConversionRatio
Namespace Prefix:	ibcp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	ibcp_FairValueOffBalanceSheetRisksAbstract
Namespace Prefix:	ibcp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The value of the number of shares held at close of period.

No definition available.

Name:	ibcp_InvestmentOwnedBalanceSharesValue
Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Non interest provision for loss reimbursement on sold loans.

No definition available.

Name:	ibcp_ProvisionForLossReimbursementOnSoldLoans
Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Reserve balance as of the reporting date for loss reimbursements on sold mortgage loans.

No definition available.

Name:	ibcp_ReserveForLossReimbursementOnSoldLoans
Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

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

Balance held at close of period in number of shares.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-12B(Column B))
-URI http://asc.fasb.org/extlink&oid=120401592&loc=d3e611197-123010

Name:	us-gaap_InvestmentOwnedBalanceShares
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Name:	us-gaap_InvestmentTypeAxis=ibcp_VISAClassAStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentTypeAxis=ibcp_VISAClassBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommitmentsToExtendCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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