Allowance for Loan Losses - Loans Modified in TDR (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 Contract	Jun. 30, 2012 Contract	Jun. 30, 2013 Contract	Jun. 30, 2012 Contract
Non Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	10	37	17	43
Recorded Investment	$ 2,585	$ 6,596	$ 5,284	$ 6,872
Non Default [Member] | Land, Farmland, Ag Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	2	1	2
Recorded Investment	458	733	458	733
Non Default [Member] | Residential / Prime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	4	20	7	24
Recorded Investment	123	2,572	894	2,818
Non Default [Member] | Residential / Subprime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	3	7	5	8
Recorded Investment	172	781	519	802
Non Default [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	5	2	5
Recorded Investment	14	2,239	17	2,239
Non Default [Member] | Consumer Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	1	2	2	3
Recorded Investment	1,818	111	3,396	120
Non Default [Member] | Multi Family [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts		1		1
Recorded Investment		160		160
Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	2	2	2	2
Recorded Investment	94	88	94	88
Default [Member] | Residential / Prime [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts	2	1	2	1
Recorded Investment	94	68	94	68
Default [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Number of Contracts		1		1
Recorded Investment		$ 20		$ 20