Foreclosed Assets - Expenses Related To Foreclosed Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loss (gain) on sale of foreclosed assets	$ (9)	$ (8)	$ (9)	$ (8)
Provision for unrealized losses	780		962	1,139
Operating expenses, net of rental income	5	8	29	54
Foreclosed assets, net	$ (776)		$ (982)	$ (1,185)