Note 4 - Debt and Equity Securities (Details) - Trust preferred issues: (USD $) In Thousands, unless otherwise specified			6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Single Issuer [Member]		Jun. 30, 2013 Pooled Issuer 1 [Member]		Jun. 30, 2013 Pooled Issuer 2 [Member]		Jun. 30, 2013 Pooled Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Class			n/a		B1		C1
Performing Banks			1		17		16
Amortized Cost	$ 1,041,834	$ 915,947	$ 300		$ 5,617		$ 3,645		$ 9,562
Fair Value	1,040,723	949,566	291		3,280		2,700		6,271
Cumulative Credit Related OTTI					$ 2,196		$ 1,542		$ 3,738
Deferrals/Defaults, Actual as a Percentage of Original Security				[1]	24.80%	[1]	21.30%	[1]
Deferrals/Defaults, Expected Percentage of Performing Collateral				[1]	0.00%	[1]	0.00%	[1]
Current Lowest Rating			BB-		C		C

[1] Represents deferrals/defaults as a percentage of the original security and expected deferrals/defaults as a percentage of performing issuers.