Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment Based on Impairment Method (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 2,732	$ 3,944
Collectively evaluated for impairment	9,137	13,355
Total ending allowance balance	11,869	17,299	20,458
Loans:
Loans individually evaluated for impairment	44,376	56,345
Loans collectively evaluated for impairment	218,750	283,471
Total ending loans balance	263,126	339,816
One-to-four units
Ending allowance balance attributable to loans:
Individually evaluated for impairment	719	1,678
Collectively evaluated for impairment	1,341	3,177
Total ending allowance balance	2,060	4,855
Loans:
Loans individually evaluated for impairment	4,576	13,246
Loans collectively evaluated for impairment	53,157	63,436
Total ending loans balance	57,733	76,682
Five or more units
Ending allowance balance attributable to loans:
Individually evaluated for impairment	125	161
Collectively evaluated for impairment	1,997	2,811
Total ending allowance balance	2,122	2,972
Loans:
Loans individually evaluated for impairment	3,766	3,837
Loans collectively evaluated for impairment	79,584	104,324
Total ending loans balance	83,350	108,161
Commercial real estate
Ending allowance balance attributable to loans:
Individually evaluated for impairment	543	255
Collectively evaluated for impairment	2,142	2,853
Total ending allowance balance	2,685	3,108
Loans:
Loans individually evaluated for impairment	10,364	7,396
Loans collectively evaluated for impairment	30,760	46,863
Total ending loans balance	41,124	54,259
Church
Ending allowance balance attributable to loans:
Individually evaluated for impairment	1,276	1,683
Collectively evaluated for impairment	3,542	4,059
Total ending allowance balance	4,818	5,742
Loans:
Loans individually evaluated for impairment	25,328	31,494
Loans collectively evaluated for impairment	50,926	57,605
Total ending loans balance	76,254	89,099
Construction
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	97
Collectively evaluated for impairment	8	152
Total ending allowance balance	8	249
Loans:
Loans individually evaluated for impairment	273	302
Loans collectively evaluated for impairment	462	3,488
Total ending loans balance	735	3,790
Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	98	247
Total ending allowance balance	98	247
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	3,826	6,896
Total ending loans balance	3,826	6,896
Consumer
Ending allowance balance attributable to loans:
Individually evaluated for impairment	69	70
Collectively evaluated for impairment	9	56
Total ending allowance balance	78	126
Loans:
Loans individually evaluated for impairment	69	70
Loans collectively evaluated for impairment	35	859
Total ending loans balance	$ 104	$ 929