Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012
Note 4 - Debt and Equity Securities (Details) - Gross unrealized losses recorded in AOCI: [Line Items]
Fair Value	$ 1,040,723		$ 949,566
Cumulative Credit OTTI Losses	6,193		6,178
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	24,120	[1]
Fair Value	22,929	[1]
Gross Unrealized Losses Recorded In AOCI	1,191	[1]
Cumulative Credit OTTI Losses	2,455	[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	5,980	[1]
Gross Unrealized Losses Recorded In AOCI	3,282	[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	33,382
Fair Value	28,909
Gross Unrealized Losses Recorded In AOCI	4,473
Cumulative Credit OTTI Losses	$ 6,193

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