Note 4 - Investment Securities (Detail) - Schedule of amortized cost and fair value of securities, by contractual maturity (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Maturity in years:
Securities Available for Sale, Amortized Cost, 1 year or less	$ 36,061	$ 21,362
Securities Available for Sale, Fair Value, 1 year or less	36,229	21,460
Securities Held to Maturity, Amortized Cost, 1 year or less	10,910	6,057
Securities Held to Maturity, Fair Value, 1 year or less	10,980	6,103
Securities Available for Sale, Amortized Cost, Over 1 to 5 years	275,954	315,777
Securities Available for Sale, Fair Value, Over 1 to 5 years	275,655	314,605
Securities Held to Maturity, Amortized Cost, Over 1 to 5 years	136,765	92,837
Securities Held to Maturity, Fair Value, Over 1 to 5 years	140,613	95,608
Securities Available for Sale, Amortized Cost, Over 5 to 10 years	60,795	64,565
Securities Available for Sale, Fair Value, Over 5 to 10 years	62,417	64,804
Securities Held to Maturity, Amortized Cost, Over 5 to 10 years	318,260	351,407
Securities Held to Maturity, Fair Value, Over 5 to 10 years	331,886	360,602
Securities Available for Sale, Amortized Cost, Over 10 years	138,743	130,103
Securities Available for Sale, Fair Value, Over 10 years	144,036	124,160
Securities Held to Maturity, Amortized Cost, Over 10 years	47,888	5,071
Securities Held to Maturity, Fair Value, Over 10 years	50,018	5,059
Securities Available for Sale, Amortized Cost, Subtotal	511,553	531,807
Securities Available for Sale, Fair Value, Subtotal	518,337	525,029
Securities Held to Maturity, Amortized Cost, Subtotal	513,823	455,372
Securities Held to Maturity, Fair Value, Subtotal	533,497	467,372
Securities Available for Sale, Amortized Cost, Mortgage-backed securities and residential collateralized mortgage obligations	149,853	135,492
Securities Available for Sale, Fair Value, Mortgage-backed securities and residential collateralized mortgage obligations	158,233	140,497
Securities Held to Maturity, Amortized Cost, Mortgage-backed securities and residential collateralized mortgage obligations	242,083	125,356
Securities Held to Maturity, Fair Value, Mortgage-backed securities and residential collateralized mortgage obligations	244,833	127,339
Securities Available for Sale, Amortized Cost, Other securities	3,221	3,479
Securities Available for Sale, Fair Value, Other securities	7,070	5,958
Securities Available for Sale, Amortized Cost, Total	664,627	670,778
Securities Available for Sale, Fair Value, Total	683,640	671,484
Securities Held to Maturity, Amortized Cost, Total	755,906	580,728
Securities Held to Maturity, Fair Value, Total	$ 778,330	$ 594,711

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Name Statement of Financial Accounting Standard (FAS)

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