Note 5 - Securities (Tables)

3 Months Ended

Mar. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Securities [Table Text Block]

	March 31, 2015
	Amortized Costs		Gross Unrealized Gains		Gross Unrealized Losses		Fair Values
Available for Sale:
U.S. Government agencies and corporations	$	210,729	$	1,445	$	1,417	$	210,757
States and political subdivisions		17,583		818		---		18,401
Mortgage-backed securities		1,665		179		---		1,844
Corporate debt securities		6,991		382		---		7,373
Other securities		189		---		68		121
Total securities available for sale	$	237,157	$	2,824	$	1,485	$	238,496

	December 31, 2014
	Amortized Costs		Gross Unrealized Gains		Gross Unrealized Losses		Fair Values
Available for Sale:
U.S. Government agencies and corporations	$	197,740	$	973	$	4,494	$	194,219
States and political subdivisions		18,529		851		---		19,380
Mortgage-backed securities		1,830		184		---		2,014
Corporate debt securities		6,991		140		27		7,104
Other securities		189		---		62		127
Total securities available for sale	$	225,279	$	2,148	$	4,583	$	222,844

Held-to-maturity Securities [Table Text Block]

	March 31, 2015
	Amortized Costs		Gross Unrealized Gains		Gross Unrealized Losses		Fair Values
Held to Maturity:
U.S. Government agencies and corporations	$	15,917	$	450	$	70	$	16,297
States and political subdivisions		138,407		7,095		543		144,959
Mortgage-backed securities		396		51		---		447
Corporate debt securities		1,415		25		---		1,440
Total securities held to maturity	$	156,135	$	7,621	$	613	$	163,143

	December 31, 2014
	Amortized Costs		Gross Unrealized Gains		Gross Unrealized Losses		Fair Values
Held to Maturity:
U.S. Government agencies and corporations	$	18,922	$	350	$	245	$	19,027
States and political subdivisions		140,702		6,823		727		146,798
Mortgage-backed securities		415		51		---		466
Corporate debt securities		1,413		1		2		1,412
Total securities held to maturity	$	161,452	$	7,225	$	974	$	167,703

Schedule of Temporary Impairment Losses, Investments [Table Text Block]

	March 31, 2015
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Temporarily Impaired Securities:
U.S. Government agencies and corporations	$	25,832	$	163	$	94,959	$	1,324
States and political subdivisions		10,274		109		9,952		434
Corporate debt securities		---		---		---		---
Other securities		---		---		121		68
Total	$	36,106	$	272	$	105,032	$	1,826

	December 31, 2014
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Temporarily Impaired Securities:
U.S. Government agencies and corporations	$	6,964	$	30	$	156,149	$	4,709
States and political subdivisions		1,222		35		19,818		692
Corporate debt securities		450		2		1,948		27
Other securities		---		---		127		62
Total	$	8,636	$	67	$	178,042	$	5,490