Note 3 - Securities (Detail) - Securities Portfolio (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Securities Available-for-Sale
Amortized Cost	$ 1,080,574
Fair Value	1,082,403	1,013,006
Securities Held-to-Maturity
Municipal securities	34,295	60,458
Municipal securities	1,728	1,019
Municipal securities	36,023	61,477
Trading Securities	14,162	14,469
US Government Corporations and Agencies Securities [Member]
Securities Available-for-Sale
Amortized Cost	508	5,060
Gross Unrealized Losses		(25)
Fair Value	508	5,035
Collateralized Mortgage Obligations [Member]
Securities Available-for-Sale
Amortized Cost	397,146	383,828
Gross Unrealized Gains	3,752	2,622
Gross Unrealized Losses	(515)	(2,346)
Fair Value	400,383	384,104
Other Residential Mortgage-Backed Securities [Member]
Securities Available-for-Sale
Amortized Cost	117,785	81,982
Gross Unrealized Gains	5,183	5,732
Gross Unrealized Losses	(68)	(23)
Fair Value	122,900	87,691
State and Municipal [Member]
Securities Available-for-Sale
Amortized Cost	495,906	464,282
Gross Unrealized Gains	24,623	26,155
Gross Unrealized Losses	(486)	(366)
Fair Value	520,043	490,071
Collateralized Debt Obligations [Member]
Securities Available-for-Sale
Amortized Cost	46,533	48,759
Gross Unrealized Losses	(34,404)	(35,365)
Fair Value	12,129	13,394
Corporate Debt Securities [Member]
Securities Available-for-Sale
Amortized Cost	13,006	27,511
Gross Unrealized Gains	2,333	2,514
Gross Unrealized Losses		(11)
Fair Value	15,339	30,014
Hedge Fund Investment [Member]
Securities Available-for-Sale
Amortized Cost	1,231	1,231
Gross Unrealized Gains	385	385
Fair Value	1,616	1,616
Other Equity Securities [Member]
Securities Available-for-Sale
Amortized Cost	8,459	958
Gross Unrealized Gains	1,026	123
Fair Value	9,485	1,081
Equity Securities [Member]
Securities Available-for-Sale
Amortized Cost	9,690	2,189
Gross Unrealized Gains	1,411	508
Fair Value	11,101	2,697
Total [Member]
Securities Available-for-Sale
Amortized Cost	1,080,574	1,013,611
Gross Unrealized Gains	37,302	37,531
Gross Unrealized Losses	(35,473)	(38,136)
Fair Value	$ 1,082,403	$ 1,013,006

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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