Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: [Line Items]
Amortized Cost	$ 1,061,918
Fair Value	1,058,554			949,566
Cumulative Credit OTTI Losses	6,923		6,193	6,178	6,753	6,938	6,922
Private Issue CMO [Member] | Credit Related OTTI Charge In The Consolidated Statements Of Income [Member]
Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: [Line Items]
Amortized Cost	21,665	[1]
Fair Value	20,194	[1]
Gross Unrealized Losses Recorded In AOCI	1,471	[1]
Cumulative Credit OTTI Losses	3,185	[1]
Credit Related OTTI Charge In The Consolidated Statements Of Income [Member] | Trust Preferred Securities [Member]
Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: [Line Items]
Amortized Cost	9,262	[1]
Fair Value	5,480	[1]
Gross Unrealized Losses Recorded In AOCI	3,782	[1]
Cumulative Credit OTTI Losses	3,738	[1]
Credit Related OTTI Charge In The Consolidated Statements Of Income [Member]
Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: [Line Items]
Amortized Cost	30,927
Fair Value	25,674
Gross Unrealized Losses Recorded In AOCI	5,253
Cumulative Credit OTTI Losses	$ 6,923

[1] The Company has recorded OTTI charges in the Consolidated Statements of Income on five private issue CMOs and two pooled trust preferred securities for which a portion of the OTTI is currently recorded in AOCI.