Income classified as other excluding interest income.

No definition available.

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Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate assets financed by the entity sold during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of the entity's revenue excluded from the scope of ASU 2014-09.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
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Balance Type:	credit
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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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

- References

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of revenue earned, classified as other, excluding interest income.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Balance Type:	credit
Period Type:	duration

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Data Type:	na
Balance Type:
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- Details

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Data Type:	na
Balance Type:
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Name:	srt_MajorCustomersAxis=ibcp_CustomerRetailMember
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Balance Type:
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Balance Type:
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Data Type:	na
Balance Type:
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REVENUE FROM CONTRACTS WITH CUSTOMERS (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Asset	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
REVENUE FROM CONTRACTS WITH CUSTOMERS [Abstract]
Percentage of revenues excluded from ASU 2014-09	82.90%	80.30%
Contract assets	$ 0
Contract liabilities	$ 0
Number of real estate assets sold during the period \| Asset	0
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	$ 27,126
Bank owned life insurance	970	$ 1,061	$ 1,124
Other	2,827
Total	8,760	$ 8,168	$ 8,603
Service Charges on Deposits Accounts [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	12,258
Overdraft Fees [Member] \| Retail [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	8,285
Overdraft Fees [Member] \| Business [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	1,567
Account Service Charges [Member] \| Retail [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	2,145
Account Service Charges [Member] \| Business [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	261
Other Deposit Related Income [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	2,992
ATM Fees [Member] \| Retail [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	1,423
ATM Fees [Member] \| Business [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	34
Other [Member] \| Retail [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	941
Other [Member] \| Business [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	594
Interchange Income [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	9,905
Investment and Insurance Commissions [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	1,971
Asset Management Revenue [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	1,100
Transaction Based Revenue [Member]
Disaggregation of Revenue Sources by Attributes [Abstract]
Revenue from contracts with customers	$ 871