CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY [Parenthetical]	3 Months Ended	9 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Common shares issued for dividend reinvestment and stock purchase plan (in shares)	3,178	3,117	3,178	8,786

Number of shares issued for dividend reinvestment and stock purchase plan during the period.

No definition available.

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