Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Interest Income
Interest and fees on loans	$ 61,325	$ 58,410	$ 178,628	$ 170,239
Interest on securities
Taxable	3,660	4,502	11,492	14,466
Tax-exempt	2,767	3,404	8,310	10,195
Other investments	1,538	2,018	3,882	4,898
Total Interest Income	69,290	68,334	202,312	199,798
Interest Expense
Deposits	21,972	24,462	63,389	70,148
Other borrowings and subordinated debt and debentures	1,957	2,018	5,262	6,253
Total Interest Expense	23,929	26,480	68,651	76,401
Net Interest Income	45,361	41,854	133,661	123,397
Provision for credit losses	1,991	1,488	4,212	2,251
Net Interest Income After Provision for Credit Losses	43,370	40,366	129,449	121,146
Non-interest Income
Interchange income	4,157	4,146	10,674	10,698
Service charges on deposit accounts	3,131	3,085	8,926	8,894
Net gains (losses) on assets
Mortgage loans	1,474	2,177	5,408	4,874
Equity securities at fair value	0	(8)	0	2,685
Securities available for sale	(36)	(145)	(355)	(414)
Mortgage loan servicing, net	74	(3,130)	(72)	1,686
Other	3,137	3,383	9,105	8,818
Total Non-interest Income	11,937	9,508	33,686	37,241
Non-interest Expense
Compensation and employee benefits	21,125	20,048	62,631	62,069
Data processing	3,784	3,379	11,360	9,891
Occupancy, net	2,127	1,893	6,396	5,853
Interchange expense	1,180	1,149	3,476	3,373
Advertising	526	581	2,220	1,860
Furniture, fixtures and equipment	892	932	2,570	2,834
Loan and collection	618	657	2,148	1,868
FDIC deposit insurance	615	664	1,963	2,141
Communications	465	519	1,526	1,633
Legal and professional	682	687	1,661	1,717
Other	2,117	2,074	6,204	4,870
Total Non-interest Expense	34,131	32,583	102,155	98,109
Income Before Income Tax	21,176	17,291	60,980	60,278
Income tax expense	3,674	3,481	11,011	11,949
Net Income	$ 17,502	$ 13,810	$ 49,969	$ 48,329
Net Income Per Common Share
Basic (in dollars per share)	$ 0.85	$ 0.66	$ 2.40	$ 2.31
Diluted (in dollars per share)	$ 0.84	$ 0.65	$ 2.38	$ 2.29

The amount of expenses incurred in the period for data processing services and related costs.

No definition available.

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

- Definition

Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from non-transaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (9) issuing stop payment orders; (10) certifying checks. This item does not include penalties assessed on the early withdrawal of time deposits.

+ References

No definition available.