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		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Real estate - residential mortgage:
Average Investment in Impaired Loans	$ 31,062	$ 29,750	$ 27,533	$ 29,077
Interest Income Recognized	32	106	64	205
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	1,700	5,128	1,856	4,462
Interest Income Recognized	7	25	12	59
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	7,743	11,951	7,875	11,577
Interest Income Recognized		1		2
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	14,759	7,699	11,961	6,302
Interest Income Recognized	18	28	31	39
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	6,438	3,795	5,306	5,601
Interest Income Recognized	5	34	11	69
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	422	1,177	535	1,135
Interest Income Recognized	2	18	10	36
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	290	2,480	447	1,931
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	4,543	4,221	5,782	7,643
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	10,803	5,128	7,158	2,426
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	4,035	947	3,153	2,871
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	265	588	265	612
One to Four Family Units [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	1,410	2,648	1,409	2,531
Interest Income Recognized	7	25	12	59
Real Estate Construction [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	3,200	7,730	2,093	3,934
Interest Income Recognized		1		2
Real Estate Commercial [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	3,956	2,571	4,803	3,876
Interest Income Recognized	18	28	31	39
Commercial Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	2,403	2,848	2,153	2,730
Interest Income Recognized	5	34	11	69
Consumer and Other Loans [Member]
Real estate - residential mortgage:
Average Investment in Impaired Loans	157	589	270	523
Interest Income Recognized	$ 2	$ 18	$ 10	$ 36