Allowance for Loan Losses - Loans Modified in TDR (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013 Contract	Sep. 30, 2012 Contract	Sep. 30, 2013 Contract	Sep. 30, 2012 Contract
Non Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	13	13	33	80
Recorded Investment	$ 1,145	$ 913	$ 7,179	$ 7,107
Non Default [Member] | Land, Farmland, Ag Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	0	0	3	2
Recorded Investment	0	0	576	732
Non Default [Member] | Residential / Prime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	6	6	11	54
Recorded Investment	376	503	1,253	3,281
Non Default [Member] | Residential / Subprime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	4	2	11	10
Recorded Investment	171	187	1,159	966
Non Default [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	2	0	3	4
Recorded Investment	591	0	798	1,711
Non Default [Member] | Consumer Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	0	5	2	10
Recorded Investment	0	223	15	417
Non Default [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1		1
Recorded Investment	7		7
Non Default [Member] | Multi Family [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	0	0	2	0
Recorded Investment	0	0	3,371	0
Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	3	5	3	6
Recorded Investment	122	271	122	339
Default [Member] | Residential / Prime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	1	1	2
Recorded Investment	40	98	40	166
Default [Member] | Residential / Subprime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	3	1	3
Recorded Investment	75	153	75	153
Default [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	1	1	1
Recorded Investment	$ 7	$ 20	$ 7	$ 20