Note 4: Loans and Allowance for Loan Losses (Detail) - Average Impaired Loans and Related Interest Income Recognized (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Real estate - residential mortgage:
Average Investment in Impaired Loans	$ 29,849	$ 27,606	$ 28,305	$ 28,587
Interest Income Recognized	28	106	92	311
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	2,707	3,640	2,141	4,188
Interest Income Recognized	5	20	17	79
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	5,723	11,597	7,157	11,584
Interest Income Recognized		8		10
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	13,358	8,697	12,426	7,101
Interest Income Recognized	18	21	49	60
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	7,493	2,968	6,035	4,723
Interest Income Recognized	4	37	15	106
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	568	704	546	991
Interest Income Recognized	1	20	11	56
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	106	1,491	334	1,784
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	770	7,794	4,111	7,694
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	9,085	3,164	7,800	2,672
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	4,774	2,861	3,693	2,868
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	417	159	316	461
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	2,601	2,149	1,807	2,404
Interest Income Recognized	5	20	17	79
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	4,953	3,803	3,046	3,890
Interest Income Recognized		8		10
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	4,273	5,533	4,626	4,429
Interest Income Recognized	18	21	49	60
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	2,719	107	2,342	1,855
Interest Income Recognized	4	37	15	106
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	151	545	230	530
Interest Income Recognized	$ 1	$ 20	$ 11	$ 56