Loans - Aging of Recorded Investment In Past Due Loans By Class of Loans (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	$ 556	$ 1,012
60 - 89 Days Past Due	818	779
Greater than 90 Days Past Due	3,839	3,768
Total Past Due	5,213	5,559
Loans Not Past Due	123,599	151,711
Nonaccrual Loans Not > 90 Days Past Due	7,927	8,301
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	21	103
60 - 89 Days Past Due	112	0
Greater than 90 Days Past Due	120	0
Total Past Due	253	103
Loans Not Past Due	17,934	25,891
Nonaccrual Loans Not > 90 Days Past Due	667	47
Single-family residential [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	302	714
60 - 89 Days Past Due	706	474
Greater than 90 Days Past Due		491
Total Past Due	1,008	1,679
Loans Not Past Due	14,417	16,535
Nonaccrual Loans Not > 90 Days Past Due	44	736
Multi-family residential [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days Past Due	2,029	3,065
Total Past Due	2,029	3,065
Loans Not Past Due	20,871	24,098
Nonaccrual Loans Not > 90 Days Past Due	3,937	4,996
Other consumer [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	61
60 - 89 Days Past Due		30
Total Past Due	61	30
Loans Not Past Due	977	1,191
Non-owner occupied [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	42	173
60 - 89 Days Past Due		275
Greater than 90 Days Past Due	1,243	68
Total Past Due	1,285	516
Loans Not Past Due	29,507	35,899
Nonaccrual Loans Not > 90 Days Past Due	1,839	1,910
Owner occupied [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Greater than 90 Days Past Due	300
Total Past Due	300
Loans Not Past Due	22,386	27,900
Nonaccrual Loans Not > 90 Days Past Due	1,293	446
Land [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Not Past Due	4,639	5,442
Originated for portfolio [Member] | Home equity lines of credit [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due		22
Greater than 90 Days Past Due	66	135
Total Past Due	66	157
Loans Not Past Due	10,734	12,126
Nonaccrual Loans Not > 90 Days Past Due	66	157
Purchased for portfolio [Member] | Home equity lines of credit [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past Due	130
Greater than 90 Days Past Due	81	9
Total Past Due	211	9
Loans Not Past Due	2,134	2,629
Nonaccrual Loans Not > 90 Days Past Due	$ 81	$ 9