Note 6 - Securities (Details) - Amortized Cost and Fair Value of Available-for-Sale Securities (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended		12 Months Ended	6 Months Ended	12 Months Ended			3 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Obligations of U.S. Government Agencies [Member]	Dec. 31, 2012 Obligations of U.S. Government Agencies [Member]	Jun. 30, 2013 Obligations of States and Political Subdivisions, Tax-exempt [Member]	Dec. 31, 2012 Obligations of States and Political Subdivisions, Tax-exempt [Member]	Jun. 30, 2013 Obligations of States and Political Subdivisions, Taxable [Member]	Dec. 31, 2012 Obligations of States and Political Subdivisions, Taxable [Member]	Jun. 30, 2013 Mortgage-backed Securities [Member]	Dec. 31, 2012 Mortgage-backed Securities [Member]	Jun. 30, 2013 Collateralized Mortgage Obligations, Issued by U.S. Government Agencies [Member]	Dec. 31, 2012 Collateralized Mortgage Obligations, Issued by U.S. Government Agencies [Member]	Jun. 30, 2013 Collateralized Debt Obligations [Member]	Jun. 30, 2013 Debt Securities [Member]	Dec. 31, 2012 Debt Securities [Member]	Jun. 30, 2013 Marketable Equity Securities [Member]	Dec. 31, 2012 Marketable Equity Securities [Member]	Dec. 31, 2012 Trust Preferred Securities Issued by Individual Institutions [Member]	Dec. 31, 2012 Collateralized Debt Obligations, Pooled Trust Preferred Securities - Senior Tranches [Member]	Mar. 31, 2013 Other Collateralized Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 465,710	$ 454,781	$ 49,016	$ 30,695	$ 132,525	$ 130,168	$ 29,976	$ 24,426	$ 63,776	$ 76,368	$ 183,792	$ 179,770	$ 660	$ 459,745	$ 448,869	$ 5,965	$ 5,912	$ 5,167	$ 1,615	$ 660
Gross Unrealized Holding Gains	10,788	18,283	412	572	3,644	7,030	273	462	2,108	3,828	1,599	3,887	0	8,036	15,783	2,752	2,500	4	0	0
Gross Unrealized Holding Losses	(6,430)	(487)	(1,458)	(50)	(1,686)	(178)	(560)	(71)	(259)	0	(2,467)	(147)	0	(6,430)	(448)	0	(39)	0	(2)	0
Fair Value	$ 470,068	$ 472,577	$ 47,970	$ 31,217	$ 134,483	$ 137,020	$ 29,689	$ 24,817	$ 65,625	$ 80,196	$ 182,924	$ 183,510	$ 660	$ 461,351	$ 464,204	$ 8,717	$ 8,373	$ 5,171	$ 1,613	$ 660