Note 3 - Securities (Details) - Securities Portfolio (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Securities Available-for-Sale
Amortized Cost	$ 1,222,725	$ 1,080,574
Gross Unrealized Gains	47,428	37,302
Gross Unrealized Losses	(46,667)	(35,473)
Fair Value	1,223,486	1,082,403
Securities Held-to-Maturity
Municipal securities	30,373	34,295
Municipal securities	1,698	1,728
Municipal securities	32,071	36,023
Municipal securities	0	0
Trading Securities	15,451	14,162
US Government Agencies Debt Securities [Member]
Securities Available-for-Sale
Amortized Cost	503	508
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	503	508
Collateralized Mortgage Obligations [Member]
Securities Available-for-Sale
Amortized Cost	543,194	397,146
Gross Unrealized Gains	1,691	3,752
Gross Unrealized Losses	(8,462)	(515)
Fair Value	536,423	400,383
Other Mortgage Backed Securities [Member]
Securities Available-for-Sale
Amortized Cost	124,773	117,785
Gross Unrealized Gains	3,540	5,183
Gross Unrealized Losses	(1,541)	(68)
Fair Value	126,772	122,900
State and Municipal [Member]
Securities Available-for-Sale
Amortized Cost	482,090	495,906
Gross Unrealized Gains	13,669	24,623
Gross Unrealized Losses	(5,000)	(486)
Fair Value	490,759	520,043
Collateralized Debt Obligations [Member]
Securities Available-for-Sale
Amortized Cost	46,532	46,533
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(31,615)	(34,404)
Fair Value	14,917	12,129
Corporate Debt Securities [Member]
Securities Available-for-Sale
Amortized Cost	13,002	13,006
Gross Unrealized Gains	2,105	2,333
Gross Unrealized Losses	0	0
Fair Value	15,107	15,339
Hedge Fund Investment [Member]
Securities Available-for-Sale
Amortized Cost	1,208	1,231
Gross Unrealized Gains	1,533	385
Gross Unrealized Losses	0	0
Fair Value	2,741	1,616
Other Equity Securities [Member]
Securities Available-for-Sale
Amortized Cost	11,423	8,459
Gross Unrealized Gains	24,890	1,026
Gross Unrealized Losses	(49)	0
Fair Value	36,264	9,485
Equity Securities [Member]
Securities Available-for-Sale
Amortized Cost	12,631	9,690
Gross Unrealized Gains	26,423	1,411
Gross Unrealized Losses	(49)	0
Fair Value	$ 39,005	$ 11,101

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

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