Note 6 - Fair Value (Details) - Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total unrealized gains/(losses) included in other comprehensive income	$ (4,715)	$ 747	$ (4,815)	$ 1,346
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of year			21,870	16,914
Balance at June 30 of each year	20,271	15,710	20,271	15,710
Total realized and unrealized gains/(losses) included in income			0	0
Total unrealized gains/(losses) included in other comprehensive income			0	0
Purchases of securities			915	2,652
Sales of securities			0	0
Calls and maturities			(2,514)	(4,076)
Net transfers in/(out) of Level 3			$ 0	$ 220