ACCOUNTING POLICIES, Nature of Operations (Details)	Dec. 31, 2021
ACCOUNTING POLICIES [Abstract]
Percentage of loan portfolio secured by real estate	69.00%

Refers to percentage of loan portfolio which was secured by real estate as on balance sheet date.

No definition available.

Name:	ibcp_PercentageOfLoanPortfolioSecuredByRealEstate
Namespace Prefix:	ibcp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant