Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Cash flows from operating activities:
Net income	$ 11,164	$ 8,667
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation	1,286	1,157
Securities amortization and accretion, net	(341)	(15)
Provision for credit losses	1,195	1,147
Gain on disposal of fixed assets	0	(7)
Mortgage banking activity	(521)	(400)
Deferred income tax (benefit) expense	(148)	(458)
Loss on sale of securities	8	0
Net change in market value of equity securities	(8)	(11)
Amortization of intangibles	57	56
Origination of loans held for sale	(33,750)	(24,685)
Proceeds from loans held for sale	34,019	25,179
Increase in cash surrender value of life insurance	(477)	(391)
Net change in other assets and other liabilities	(1,295)	(2,305)
Net cash flows from operating activities	11,189	7,934
Cash flows from investing activities:
Purchases	(21,068)	(40,292)
Maturities, calls and principal pay downs	41,477	38,548
Proceeds from sales of available-for-sale securities	2,158	0
Principal pay downs	859	887
Redemption of equity securities	400	0
Proceeds from redemption of FHLB stock	836	114
Purchases of FHLB stock	(1,326)	(597)
Net increase in loans	(124,270)	(55,017)
Purchase of bank owned life insurance	(1,920)	(2,375)
Acquisition of premises and equipment	(1,635)	(3,071)
Disposal of premises and equipment	0	30
Proceeds from sale of other real estate and repossessed assets owned	0	76
Net cash flows used in investing activities	(104,489)	(61,697)
Cash flows from financing activities:
Net increase in deposit accounts	84,144	63,838
Net change in short-term borrowings	13,699	(14,496)
Proceeds from Federal Home Loan Bank advances	26,000	19,500
Repayments of Federal Home Loan Bank advances	(21,544)	(10,658)
Proceeds from dividend reinvestment and stock purchase plan	0	147
Dividends paid	(2,644)	(2,383)
Net cash flows from financing activities	99,655	55,948
Increase in cash and cash equivalents	6,355	2,185
Cash and cash equivalents, beginning of year	19,908	17,723
Cash and cash equivalents, end of year	26,263	19,908
Cash paid during the period:
Interest	19,814	19,181
Income taxes	1,865	1,595
Non-cash items:
Transfer from loans to other repossessed assets	0	76
Issuance of treasury stock for stock awards	$ 399	$ 377

The fair value of treasury stock issued for stock awards.

No definition available.

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Namespace Prefix:	cbkm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.