Loans - Presentation of Loans Individually Evaluated for Impairment by Class (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	$ 45,671	$ 53,027	$ 45,671	$ 53,027	$ 71,140
With no specific allowance recorded, Recorded Investment	33,197	40,861	33,197	40,861	48,081
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	37,751	60,396	41,142	73,674
With no specific allowance recorded, Interest income recognized	243	262	658	607
With no specific allowance recorded, Cash basis income recognized	350	351	887	879
With a specific allowance recorded, Unpaid principal balance	15,118	36,316	15,118	36,316	18,115
With a specific allowance recorded, Recorded investment	13,130	18,383	13,130	18,383	12,936
With a specific allowance recorded, Allowance for loan losses allocated	2,423	2,129	2,423	2,129	3,024
With a specific allowance recorded, Average recorded investment	8,871	33,579	12,580	46,941
With a specific allowance recorded, Interest income recognized	141	23	275	70
With a specific allowance recorded, Cash basis income recognized	142	30	287	133
Total Unpaid Principal Balance	60,789	89,343	60,789	89,343	89,255
Total Recorded Investment	46,327	59,244	46,327	59,244	61,017
Total Allowance for Loan Losses Allocated	2,423	2,129	2,423	2,129	3,024
Total Average Recorded Investment	46,622	93,975	53,722	120,615
Total Interest Income, Accrual Method	384	285	933	677
Total cash basis income recognized	492	381	1,174	1,012
Permanent Real Estate Loans [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	25,717	33,529	25,717	33,529	37,662
With no specific allowance recorded, Recorded Investment	18,826	31,065	18,826	31,065	34,467
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	21,386	47,751	26,183	57,931
With no specific allowance recorded, Interest income recognized	130	203	347	446
With no specific allowance recorded, Cash basis income recognized	189	228	438	535
With a specific allowance recorded, Unpaid principal balance	7,805	13,782	7,805	13,782	10,862
With a specific allowance recorded, Recorded investment	7,433	10,497	7,433	10,497	8,546
With a specific allowance recorded, Allowance for loan losses allocated	1,222	1,281	1,222	1,281	2,380
With a specific allowance recorded, Average recorded investment	4,762	23,126	8,523	33,245
With a specific allowance recorded, Interest income recognized	98	18	192	55
With a specific allowance recorded, Cash basis income recognized	99	22	201	103
Permanent Real Estate Loans [Member] | One-to Four-Family Residential [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	14,687	17,027	14,687	17,027	18,672
With no specific allowance recorded, Recorded Investment	12,469	15,594	12,469	15,594	16,947
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	14,977	22,316	16,088	25,431
With no specific allowance recorded, Interest income recognized	128	194	333	424
With no specific allowance recorded, Cash basis income recognized	165	205	385	461
With a specific allowance recorded, Unpaid principal balance	6,670		6,670		735
With a specific allowance recorded, Recorded investment	6,665		6,665		735
With a specific allowance recorded, Allowance for loan losses allocated	1,092		1,092		260
With a specific allowance recorded, Average recorded investment	3,338	1,802	2,036	1,489
With a specific allowance recorded, Interest income recognized	98		192
With a specific allowance recorded, Cash basis income recognized	98		193
Permanent Real Estate Loans [Member] | Multi-Family Residential [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	737	610	737	610	1,173
With no specific allowance recorded, Recorded Investment	643	515	643	515	1,078
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	652	2,688	766	3,363
With no specific allowance recorded, Interest income recognized			2
With no specific allowance recorded, Cash basis income recognized	4	1	9	9
With a specific allowance recorded, Unpaid principal balance	185	1,026	185	1,026	996
With a specific allowance recorded, Recorded investment	85	1,011	85	1,011	981
With a specific allowance recorded, Allowance for loan losses allocated	25	57	25	57	57
With a specific allowance recorded, Average recorded investment	85	3,102	554	2,742
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized				17
Permanent Real Estate Loans [Member] | Nonresidential [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	6,380	11,308	6,380	11,308	13,240
With no specific allowance recorded, Recorded Investment	5,227	11,145	5,227	11,145	12,638
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	270	17,943	7,209	23,348
With no specific allowance recorded, Interest income recognized	2	9	12	22
With no specific allowance recorded, Cash basis income recognized	20	22	44	62
With a specific allowance recorded, Unpaid principal balance	950	8,168	950	8,168	5,218
With a specific allowance recorded, Recorded investment	683	7,115	683	7,115	4,703
With a specific allowance recorded, Allowance for loan losses allocated	105	956	105	956	1,336
With a specific allowance recorded, Average recorded investment	1,339	15,467	4,869	25,788
With a specific allowance recorded, Interest income recognized		18		55
With a specific allowance recorded, Cash basis income recognized	1	22	8	74
Permanent Real Estate Loans [Member] | Land [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	3,913	4,584	3,913	4,584	4,577
With no specific allowance recorded, Recorded Investment	487	3,811	487	3,811	3,804
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	487	4,804	2,120	5,789
With no specific allowance recorded, Interest income recognized
With no specific allowance recorded, Cash basis income recognized				3
With a specific allowance recorded, Unpaid principal balance		4,588		4,588	3,913
With a specific allowance recorded, Recorded investment		2,371		2,371	2,127
With a specific allowance recorded, Allowance for loan losses allocated		268		268	727
With a specific allowance recorded, Average recorded investment		2,755	1,064	3,226
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized				12
Construction Loans [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	1,501	7,052	1,501	7,052	18,483
With no specific allowance recorded, Recorded Investment	1,092	2,553	1,092	2,553	3,580
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	1,587	5,157	2,070	8,289
With no specific allowance recorded, Interest income recognized		3		9
With no specific allowance recorded, Cash basis income recognized		7	2	21
With a specific allowance recorded, Unpaid principal balance	3,829	21,648	3,829	21,648	6,455
With a specific allowance recorded, Recorded investment	2,241	7,427	2,241	7,427	3,967
With a specific allowance recorded, Allowance for loan losses allocated	677	664	677	664	478
With a specific allowance recorded, Average recorded investment	2,279	9,913	2,984	13,032
With a specific allowance recorded, Interest income recognized		5		15
With a specific allowance recorded, Cash basis income recognized		8		27
Construction Loans [Member] | One-to Four-Family Residential [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	1,501	6,465	1,501	6,465	17,912
With no specific allowance recorded, Recorded Investment	1,092	2,553	1,092	2,553	3,580
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	1,587	5,157	2,070	8,289
With no specific allowance recorded, Interest income recognized		3		9
With no specific allowance recorded, Cash basis income recognized		7	2	21
With a specific allowance recorded, Unpaid principal balance	3,829	21,648	3,829	21,648	6,455
With a specific allowance recorded, Recorded investment	2,241	7,427	2,241	7,427	3,967
With a specific allowance recorded, Allowance for loan losses allocated	677	664	677	664	478
With a specific allowance recorded, Average recorded investment	2,279	9,913	2,984	13,032
With a specific allowance recorded, Interest income recognized		5		15
With a specific allowance recorded, Cash basis income recognized		8		27
Construction Loans [Member] | Multi-Family and Nonresidential [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance		587		587	571
With no specific allowance recorded, Recorded Investment
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment
With no specific allowance recorded, Interest income recognized
With no specific allowance recorded, Cash basis income recognized
With a specific allowance recorded, Unpaid principal balance
With a specific allowance recorded, Recorded investment
With a specific allowance recorded, Allowance for loan losses allocated
With a specific allowance recorded, Average recorded investment
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized
Consumer Loans [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	9,555	7,082	9,555	7,082	10,012
With no specific allowance recorded, Recorded Investment	8,951	5,822	8,951	5,822	8,784
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	10,357	5,925	9,903	5,162
With no specific allowance recorded, Interest income recognized	113	50	310	133
With no specific allowance recorded, Cash basis income recognized	125	85	350	214
With a specific allowance recorded, Unpaid principal balance	3,484	88	3,484	88
With a specific allowance recorded, Recorded investment	3,456	36	3,456	36
With a specific allowance recorded, Allowance for loan losses allocated	524	18	524	18
With a specific allowance recorded, Average recorded investment	1,728	36	865	157
With a specific allowance recorded, Interest income recognized	43		83
With a specific allowance recorded, Cash basis income recognized	43		86
Consumer Loans [Member] | Home Equity [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	9,073	5,921	9,073	5,921	8,867
With no specific allowance recorded, Recorded Investment	8,511	4,956	8,511	4,956	7,958
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	9,467	4,953	8,942	4,365
With no specific allowance recorded, Interest income recognized	109	50	300	133
With no specific allowance recorded, Cash basis income recognized	116	64	328	163
With a specific allowance recorded, Unpaid principal balance	2,728		2,728
With a specific allowance recorded, Recorded investment	2,728		2,728
With a specific allowance recorded, Allowance for loan losses allocated	365		365
With a specific allowance recorded, Average recorded investment	1,364		683
With a specific allowance recorded, Interest income recognized	38		69
With a specific allowance recorded, Cash basis income recognized	38		72
Consumer Loans [Member] | Auto [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	50	72	50	72	68
With no specific allowance recorded, Recorded Investment	33	52	33	52	44
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	39	55	40	56
With no specific allowance recorded, Interest income recognized			1
With no specific allowance recorded, Cash basis income recognized	1	1	3	4
With a specific allowance recorded, Unpaid principal balance
With a specific allowance recorded, Recorded investment
With a specific allowance recorded, Allowance for loan losses allocated
With a specific allowance recorded, Average recorded investment
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized
Consumer Loans [Member] | Marine [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	162	170	162	170	190
With no specific allowance recorded, Recorded Investment	162	170	162	170	190
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	174	262	182	220
With no specific allowance recorded, Interest income recognized
With no specific allowance recorded, Cash basis income recognized	2	4	7	9
With a specific allowance recorded, Unpaid principal balance
With a specific allowance recorded, Recorded investment
With a specific allowance recorded, Allowance for loan losses allocated
With a specific allowance recorded, Average recorded investment				121
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized
Consumer Loans [Member] | Recreational Vehicles [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	270	912	270	912	887
With no specific allowance recorded, Recorded Investment	245	637	245	637	592
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	677	648	737	514
With no specific allowance recorded, Interest income recognized	4		9
With no specific allowance recorded, Cash basis income recognized	6	16	12	37
With a specific allowance recorded, Unpaid principal balance	756	88	756	88
With a specific allowance recorded, Recorded investment	728	36	728	36
With a specific allowance recorded, Allowance for loan losses allocated	159	18	159	18
With a specific allowance recorded, Average recorded investment	364	36	182	36
With a specific allowance recorded, Interest income recognized	5		14
With a specific allowance recorded, Cash basis income recognized	5		14
Consumer Loans [Member] | Others [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance		7		7
With no specific allowance recorded, Recorded Investment		7		7
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment		7	2	7
With no specific allowance recorded, Interest income recognized
With no specific allowance recorded, Cash basis income recognized				1
With a specific allowance recorded, Unpaid principal balance
With a specific allowance recorded, Recorded investment
With a specific allowance recorded, Allowance for loan losses allocated
With a specific allowance recorded, Average recorded investment
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized
Commercial Loans [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	8,898	5,364	8,898	5,364	4,983
With no specific allowance recorded, Recorded Investment	4,328	1,421	4,328	1,421	1,250
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	4,421	1,563	2,986	2,292
With no specific allowance recorded, Interest income recognized		6	1	19
With no specific allowance recorded, Cash basis income recognized	36	31	97	109
With a specific allowance recorded, Unpaid principal balance		798		798	798
With a specific allowance recorded, Recorded investment		423		423	423
With a specific allowance recorded, Allowance for loan losses allocated		166		166	166
With a specific allowance recorded, Average recorded investment	102	504	208	507
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized				3
Commercial Loans [Member] | Secured [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	4,701	2,298	4,701	2,298	2,122
With no specific allowance recorded, Recorded Investment	4,328	1,378	4,328	1,378	1,212
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	4,420	1,438	2,798	1,948
With no specific allowance recorded, Interest income recognized		6		18
With no specific allowance recorded, Cash basis income recognized	8	28	41	97
With a specific allowance recorded, Unpaid principal balance		798		798	798
With a specific allowance recorded, Recorded investment		423		423	423
With a specific allowance recorded, Allowance for loan losses allocated		166		166	166
With a specific allowance recorded, Average recorded investment	102	504	208	488
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized				3
Commercial Loans [Member] | Unsecured [Member]
Schedule Of Financial Receivables [Line Items]
With no specific allowance recorded, Unpaid principal Balance	4,197	3,066	4,197	3,066	2,861
With no specific allowance recorded, Recorded Investment		43		43	38
With no specific allowance recorded, Allowance for loan losses allocated
With no specific allowance recorded, Average recorded investment	1	125	188	344
With no specific allowance recorded, Interest income recognized			1	1
With no specific allowance recorded, Cash basis income recognized	28	3	56	12
With a specific allowance recorded, Unpaid principal balance
With a specific allowance recorded, Recorded investment
With a specific allowance recorded, Allowance for loan losses allocated
With a specific allowance recorded, Average recorded investment				19
With a specific allowance recorded, Interest income recognized
With a specific allowance recorded, Cash basis income recognized