Note 12 - Fair Value (Detail) - Carrying Value And Estimated Fair Values Of Financial Instruments (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2009
Financial Assets
Cash and cash equivalents	$ 174,911	$ 193,609	$ 197,548	$ 151,725
Investment securities held-to-maturity	4,046
Other investments	5,774	6,484
Loans held-for-sale		1,200
Cash value of bank owned life insurance	32,456	31,427
Accrued interest receivable	3,938	4,327
Loans held-for-investment, net	1,071,313	1,016,295
Financial Liabilities
Junior subordinated debentures					36,100
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Financial Assets
Cash and cash equivalents	174,911	193,609
Investment securities held-to-maturity	4,046	4,046
Other investments	5,774	6,484
Loans held-for-sale		1,200
Cash value of bank owned life insurance	32,456	31,427
Accrued interest receivable	3,938	4,327
Loans held-for-investment, net	1,071,313	1,015,095
Financial Liabilities
Deposit transaction accounts	811,781	744,833
Junior subordinated debentures	36,083	36,083
Accrued interest payable	258	310
Time deposits	453,277	506,742
Other borrowings	26,000	26,315
Portion at Fair Value, Fair Value Disclosure [Member]
Financial Assets
Cash and cash equivalents	174,911	193,609
Investment securities held-to-maturity	4,772	4,536
Other investments	5,774	6,484
Loans held-for-sale		1,498
Cash value of bank owned life insurance	32,456	31,427
Accrued interest receivable	3,938	4,327
Loans held-for-investment, net	1,051,039	968,434
Financial Liabilities
Deposit transaction accounts	811,781	744,833
Junior subordinated debentures	36,083	36,083
Accrued interest payable	258	310
Time deposits	453,277	511,050
Other borrowings	25,991	26,206
Off-balance sheet financial instruments
Unfunded loan commitments, including unfunded lines of credit	173	236
Standby letters of credit	$ 45	$ 69