Deposits - Summary of Composition of Deposits (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]
Transaction deposit accounts	$ 9	$ 14	$ 30	$ 97
Money market deposit accounts	8	38	40	171
Savings deposit accounts	2	4	6	31
Time deposit accounts	1,207	2,211	3,882	7,168
Total interest paid on deposits	$ 1,226	$ 2,267	$ 3,958	$ 7,467