Loans - Loan Balances by Loan Classification Allocated Between Past Due Performing and Non-performing (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	$ 536,563	$ 496,922
30-89 Days Past Due	1,055	1,687
90 Days + past due and Accruing	1,486
Non-accrual Loans	7,158	3,175	$ 1,117
Special Mention	4,924	9,863
Impaired Loans Currently Performing Substandard	16,325	34,192
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	567,511	545,839
One-to-Four Family Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	142,796	145,372
30-89 Days Past Due	325	757
Non-accrual Loans	1,427	1,501	407
Special Mention	330	203
Impaired Loans Currently Performing Substandard	1,492	2,718
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	146,370	150,551
Home Equity Line of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	32,703	33,338
30-89 Days Past Due		143
Non-accrual Loans	48		31
Impaired Loans Currently Performing Substandard	225	757
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	32,976	34,238
Junior Liens [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	1,746	2,025
Special Mention	36	40
Impaired Loans Currently Performing Substandard	16	37
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	1,798	2,102
Multi-Family [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	20,272	20,066
Non-accrual Loans	1,968	95
Special Mention		2,904
Impaired Loans Currently Performing Substandard	1,126	2,926
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	23,366	25,991
Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	32,669	24,241
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	32,669	24,241
Land [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	11,604	14,674
30-89 Days Past Due		654
90 Days + past due and Accruing	1,486
Non-accrual Loans	1,680	215	301
Special Mention	43	362
Impaired Loans Currently Performing Substandard	7,841	10,749
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	22,654	26,654
Non-Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	147,938	131,854
Non-accrual Loans	672	1,159	101
Special Mention	4,158	5,492
Impaired Loans Currently Performing Substandard	4,346	12,091
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	157,114	150,596
Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	40,309	40,057
30-89 Days Past Due		64
Non-accrual Loans	168	115	12
Special Mention		516
Impaired Loans Currently Performing Substandard	162	2,122
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	40,639	42,874
Consumer Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	18,142	14,104
30-89 Days Past Due	29	14
Non-accrual Loans			2
Special Mention		21
Impaired Loans Currently Performing Substandard	204	299
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	18,375	14,438
Commercial Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Currently Performing	88,384	71,191
30-89 Days Past Due	701	55
Non-accrual Loans	1,195	90	$ 263
Special Mention	357	325
Impaired Loans Currently Performing Substandard	913	2,493
Impaired Loans Currently Performing Doubtful	0	0
Total loans, gross	$ 91,550	$ 74,154