Loans - Allowance for Loan Loss Account by Loan (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	$ 10,648	$ 11,262	$ 11,262
Charge off	(2,370)	(2,428)	(3,684)
Recoveries	339	465	795
General Provision	156		2,777
Specific Provision	626		(502)
Ending balance	9,399	10,568	10,648
One-to-four Family Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	2,490	2,640	2,640
Charge off	(368)	(264)	(379)
Recoveries	8	43	81
General Provision	149		324
Specific Provision	115		(176)
Ending balance	2,394		2,490
Home Equity Line of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	374	408	408
Charge off	(6)	(53)	(67)
Recoveries	2	3	6
General Provision	30		6
Specific Provision	(11)		21
Ending balance	389		374
Junior liens [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	230	277	277
Charge off	(84)	(1)	(1)
Recoveries	24	2	4
General Provision	(132)
Specific Provision	25		(50)
Ending balance	63		230
Multi-family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	524	1,201	1,201
Charge off	(38)	(416)	(417)
Recoveries	163
General Provision	(257)		429
Specific Provision	(159)		(689)
Ending balance	233		524
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	256	139	139
General Provision	(61)		117
Specific Provision	(128)
Ending balance	67		256
Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	2,184	1,332	1,332
Charge off	(393)	(779)	(1,033)
Recoveries	5	234	405
General Provision	(231)		635
Specific Provision	235		845
Ending balance	1,800		2,184
Non-Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	2,914	3,671	3,671
Charge off	(1,039)	(579)	(1,120)
Recoveries	14	100	137
General Provision	580		718
Specific Provision	469		(492)
Ending balance	2,938		2,914
Farmland [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	719
General Provision	(271)		315
Specific Provision	14		404
Ending balance	462		719
Consumer loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	338	262	262
Charge off	(386)		(510)
Recoveries	119		150
General Provision	307		404
Specific Provision	102		32
Ending balance	480		338
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	619	1,332	1,332
Charge off	(56)		(157)
Recoveries	4	4	12
General Provision	42		(171)
Specific Provision	(36)		(397)
Ending balance	$ 573		$ 619