Note 5. Allowances For Loan And Real Estate Losses (Detail) - Allowances for Loan Losses (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Provisions for estimated losses			$ 308,000	$ 3,000,000
Loan and Leases [Member]
Balance—beginning of year	18,340,000	29,113,000	20,818,000	31,084,000
Balance—end of period	17,264,000	29,598,000	17,264,000	29,598,000
Provisions for estimated losses	6,000	631,000	22,000	791,000
Recoveries	127,000	98,000	897,000	627,000
Losses charged off	(1,209,000)	(244,000)	(4,473,000)	(2,904,000)
Real Estate [Member]
Balance—beginning of year	20,501,000	8,853,000	20,934,000	7,841,000
Balance—end of period	19,649,000	9,634,000	19,649,000	9,634,000
Provisions for estimated losses	280,000	1,355,000	308,000	2,999,000
Losses charged off	$ (1,132,000)	$ (574,000)	$ (1,593,000)	$ (1,206,000)