Note 7 - Investment Securities (Details) (USD $)	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Note 7 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Gross Unrealized Loss	$ 10,300,000
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	1,152,000	856,000
Available-for-sale Securities	561,506,000	573,108,000
Corporate Debt Securities [Member]
Note 7 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	1,100,000
AFS Gross Unrealized Losses [Member]
Note 7 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss) before Taxes	(9,000,000)
Single Issuer Corporate Debt Security [Member]
Note 7 - Investment Securities (Details) [Line Items]
Available-for-sale Securities	$ 4,800,000