Note 4 - Investment Securities (Details) - Municipal Securities Portfolio (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, fair value	$ 272,483	$ 292,299
Municipal General Obligation Bonds [Member] | TEXAS
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	11,252
Investment securities, fair value	11,880
Municipal General Obligation Bonds [Member] | PENNSYLVANIA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	6,492
Investment securities, fair value	6,597
Municipal General Obligation Bonds [Member] | CALIFORNIA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	3,563
Investment securities, fair value	3,640
Municipal General Obligation Bonds [Member] | NORTH CAROLINA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,993
Investment securities, fair value	3,061
Municipal General Obligation Bonds [Member] | NEW YORK
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,579
Investment securities, fair value	2,669
Municipal General Obligation Bonds [Member] | SOUTH CAROLINA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,295
Investment securities, fair value	2,371
Municipal General Obligation Bonds [Member] | Other States [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	10,742
Investment securities, fair value	11,124
Municipal General Obligation Bonds [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	39,916
Investment securities, fair value	41,342
Municipal Revenue Bonds [Member] | TEXAS
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,766
Investment securities, fair value	2,854
Municipal Revenue Bonds [Member] | PENNSYLVANIA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	1,774
Investment securities, fair value	1,871
Municipal Revenue Bonds [Member] | NORTH CAROLINA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	4,964
Investment securities, fair value	5,220
Municipal Revenue Bonds [Member] | NEW YORK
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,796
Investment securities, fair value	2,865
Municipal Revenue Bonds [Member] | FLORIDA
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	1,663
Investment securities, fair value	1,768
Municipal Revenue Bonds [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	13,963
Investment securities, fair value	14,578
US States and Political Subdivisions Debt Securities [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	53,879
Investment securities, fair value	55,920
Municipal Revenue Bonds - Refunding Bonds [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	4,483
Investment securities, fair value	4,738
Municipal Revenue Bonds - University and College [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,766
Investment securities, fair value	2,854
Municipal Revenue Bonds - Public Improvements [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,177
Investment securities, fair value	2,266
Municipal Revenue Bonds - Pension Funding [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	1,774
Investment securities, fair value	1,871
Municipal Revenue Bonds - Other [Member]
Note 4 - Investment Securities (Details) - Municipal Securities Portfolio [Line Items]
Investment securities, amortized cost	2,763
Investment securities, fair value	$ 2,849