Note 9 - Commitments and Financial Instruments with Off-Balance-Sheet Risk (Detail)	9 Months Ended
Sep. 30, 2012
Recourse period for early payment default, minimum	90
Recourse period for early payment default, maximum	one

The minimum recourse period for early payment default on residential loans sold to third parties.

No definition available.

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Namespace Prefix:	cffi_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration