CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY [Parenthetical] - shares	3 Months Ended	9 Months Ended
Mar. 31, 2016	Mar. 31, 2016
Dividend Reinvestment Plan And Restricted Award Forfeited And Expired (in shares)	30	305

Stock Issued During Period Shares Dividend Reinvestment Plan And Restricted Award Forfeited And Expired.

No definition available.

Name:	cbkm_StockIssuedDuringPeriodSharesDividendReinvestmentPlanAndRestrictedAwardForfeitedAndExpired
Namespace Prefix:	cbkm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration