Note 3 - Investment Securities Available-for-Sale (Details) - Securities in Continuous Unrealized Loss Position (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 3 - Investment Securities Available-for-Sale (Details) - Securities in Continuous Unrealized Loss Position [Line Items]
Less than 12 Months Estimated Fair Value	$ 19,418	$ 56,619
Less than 12 Months Unrealized Losses	84	242
12 Months or Greater Estimated Fair Value	76,319	98,693
12 Months or Greater Unrealized Losses	1,124	2,435
Total Estimated Fair Value	95,737	155,312
Total Unrealized Losses	1,208	2,677
Residential Mortgage Backed Securities [Member]
Note 3 - Investment Securities Available-for-Sale (Details) - Securities in Continuous Unrealized Loss Position [Line Items]
Less than 12 Months Estimated Fair Value	13,798	49,644
Less than 12 Months Unrealized Losses	35	221
12 Months or Greater Estimated Fair Value	76,319	86,028
12 Months or Greater Unrealized Losses	1,124	2,295
Total Estimated Fair Value	90,117	135,672
Total Unrealized Losses	1,159	2,516
US States and Political Subdivisions Debt Securities [Member]
Note 3 - Investment Securities Available-for-Sale (Details) - Securities in Continuous Unrealized Loss Position [Line Items]
Less than 12 Months Estimated Fair Value	5,620	4,974
Less than 12 Months Unrealized Losses	49	14
12 Months or Greater Estimated Fair Value		10,915
12 Months or Greater Unrealized Losses		107
Total Estimated Fair Value	5,620	15,889
Total Unrealized Losses	49	121
US Government Agencies Debt Securities [Member]
Note 3 - Investment Securities Available-for-Sale (Details) - Securities in Continuous Unrealized Loss Position [Line Items]
Less than 12 Months Estimated Fair Value		2,001
Less than 12 Months Unrealized Losses		7
12 Months or Greater Estimated Fair Value		1,750
12 Months or Greater Unrealized Losses		33
Total Estimated Fair Value		3,751
Total Unrealized Losses		$ 40

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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