Note 4 - Debt and Equity Securities (Details) - Trust Preferred Issues (USD $) In Thousands, unless otherwise specified								9 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2014 Trust Preferred Securities [Member]	Sep. 30, 2014 Single Issuer [Member]	Sep. 30, 2014 Pooled Issuer 1 [Member]	Sep. 30, 2014 Pooled Issuer 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Class								n/a	B1	C1
Performing Banks								1	15	16
Amortized Cost	$ 987,576		$ 1,032,924				$ 9,562	$ 300	$ 5,617	$ 3,645
Fair Value	984,377		1,017,790				6,793	293	3,200	3,300
Cumulative Credit Related OTTI	$ 3,738	$ 3,738	$ 3,738	$ 6,923	$ 6,193	$ 6,178	$ 3,738		$ 2,383	$ 1,355
Deferrals/Defaults, Actual as a Percentage of Original Security								0.00%	22.50%	17.90%
Deferrals/Defaults, Expected Percentage of Performing Collateral								0.00%	0.00%	0.00%
Current Lowest Rating								BB-	C	C