Note 20 - Regulatory Capital (Details)	12 Months Ended
Dec. 31, 2014
Disclosure Text Block [Abstract]
Advances From Subsidiaries Limited to as Percentage of Bank Tier One and Two Capital	10.00%

Advances from subsidiaries limited to as percentage of bank tier one and two capital.

No definition available.

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Namespace Prefix:	boch_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration