Cash and due from banks (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Cash and Due from Banks [Abstract]
Federal reserve bank mandated reserve amount	$ 16.8	$ 8.0

The mandated reserve amounts required of federal reserve bank.

No definition available.

Name:	cacb_FederalReserveBankMandatedReserveAmount
Namespace Prefix:	cacb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant