Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	$ 350,152	$ 348,190
Unrealized Gains	3,292	5,658
Unrealized Losses	(2,434)	(170)
Carrying Value	351,010	353,678
US Government Agencies Debt Securities [Member]
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	97,898	105,629
Unrealized Gains	597	1,271
Unrealized Losses	(345)	(15)
Carrying Value	98,150	106,885
US States and Political Subdivisions Debt Securities [Member]
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	148,622	116,123
Unrealized Gains	898	1,786
Unrealized Losses	(1,784)	(95)
Carrying Value	147,736	117,814
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	60,061	64,550
Unrealized Gains	1,021	1,729
Unrealized Losses	(264)	(2)
Carrying Value	60,818	66,277
Collateralized Mortgage Obligations [Member]
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	42,182	60,278
Unrealized Gains	546	810
Unrealized Losses	(41)	(58)
Carrying Value	42,687	61,030
Equity Securities [Member]
Note 2 - Investments (Details) - Unrealized Gains and Losses in Investments [Line Items]
Amortized Cost	1,389	1,610
Unrealized Gains	230	62
Unrealized Losses	0	0
Carrying Value	$ 1,619	$ 1,672