Note 6 - Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Detail) - TDRs by Class (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Restructured loans still accruing interest	$ 7,811		$ 17,864
Commercial And Industrial [Member]
Restructured loans still accruing interest	175	[1]	1,451	[1]
Restructured loans non-accrual	1,380	[2]	897	[2]
Restructured loans	1,555		2,348
Agricultural [Member]
Restructured loans still accruing interest		[1]		[1]
Restructured loans non-accrual		[2]		[2]
Office Retail And Industrial [Member]
Restructured loans still accruing interest	620	[1]	1,742	[1]
Restructured loans non-accrual	220	[2]		[2]
Restructured loans	840		1,742
Multi-Family [Member]
Restructured loans still accruing interest		[1]	11,107	[1]
Restructured loans non-accrual	1,758	[2]	1,758	[2]
Restructured loans	1,758		12,865
Residential Construction [Member]
Restructured loans still accruing interest		[1]		[1]
Restructured loans non-accrual		[2]		[2]
Commercial Construction [Member]
Restructured loans still accruing interest		[1]		[1]
Restructured loans non-accrual	14,006	[2]	14,006	[2]
Restructured loans	14,006		14,006
Other Commercial Real Estate [Member]
Restructured loans still accruing interest	5,883	[1]	227	[1]
Restructured loans non-accrual	6,025	[2]	11,417	[2]
Restructured loans	11,908		11,644
Total Commercial Real Estate [Member]
Restructured loans still accruing interest	6,503	[1]	13,076	[1]
Restructured loans non-accrual	22,009	[2]	27,181	[2]
Restructured loans	28,512		40,257
Total Corporate Loans [Member]
Restructured loans still accruing interest	6,678	[1]	14,527	[1]
Restructured loans non-accrual	23,389	[2]	28,078	[2]
Restructured loans	30,067		42,605
Home Equity1 [Member]
Restructured loans still accruing interest	21	[1]	1,093	[1]
Restructured loans non-accrual	395	[2]	471	[2]
Restructured loans	416		1,564
1-4 Family Mortgages [Member]
Restructured loans still accruing interest	1,112	[1]	2,089	[1]
Restructured loans non-accrual	1,077	[2]	1,293	[2]
Restructured loans	2,189		3,382
Installment Loans [Member]
Restructured loans still accruing interest		[1]	155	[1]
Restructured loans non-accrual		[2]		[2]
Restructured loans			155
Consumer [Member]
Restructured loans still accruing interest	1,133	[1]	3,337	[1]
Restructured loans non-accrual	1,472	[2]	1,764	[2]
Restructured loans	2,605		5,101
Total Loans [Member]
Restructured loans still accruing interest	7,811	[1]	17,864	[1]
Restructured loans non-accrual	24,861	[2]	29,842	[2]
Restructured loans	$ 32,672		$ 47,706

[1] These loans are still accruing interest.

[2] These loans are included in non-accrual loans in the preceding tables.