Note 3 - Investment Securities (Tables)

12 Months Ended

Dec. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Investment [Table Text Block]

	Years Ended December 31
	2013									2012
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Estimated Fair Value
Held-to-Maturity
U.S. Government agencies	$	395,198	$	50	$	(10,535	)	$	384,713	$	288,098	$	135	$	(679	)	$	287,554
Mortgage-backed securities		34,425		17		(442	)		34,000		49		1		-			50
State and political subdivisions		315,445		2,165		(5,498	)		312,112		207,374		5,140		(160	)		212,354
Other securities		620		-		-			620		620		-		-			620
Total	$	745,688	$	2,232	$	(16,475	)	$	731,445	$	496,141	$	5,276	$	(839	)	$	500,578
Available-for-Sale
U.S. Treasury	$	4,001	$	-	$	(16	)	$	3,985	$	-	$	-	$	-		$	-
U.S. Government agencies		183,781		8		(5,572	)		178,217		152,708		65		(292	)		152,481
Mortgage-backed securities		1,735		156		-			1,891		20,436		287		(89	)		20,634
State and political subdivisions		7,860		4		(3	)		7,861		2,989		-		(1	)		2,988
Other securities		19,840		484		(1	)		20,323		14,787		456		(4	)		15,239
Total	$	217,217	$	652	$	(5,592	)	$	212,277	$	190,920	$	808	$	(386	)	$	191,342

Schedule of Unrealized Loss on Investments [Table Text Block]

	Less Than 12 Months				12 Months or More				Total
(In thousands)	Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses
December 31, 2013
Held-to-Maturity
U.S. Government agencies	$	258,474	$	6,405	$	114,339	$	4,130	$	372,814	$	10,535
Mortgage-backed securities		32,053		442		-		-		32,053		442
State and political subdivisions		130,457		5,311		4,466		187		134,923		5,498
Total	$	420,984	$	12,158	$	118,805	$	4,317	$	539,790	$	16,475
Available-for-Sale
U.S. Treasury	$	3,985	$	16	$	-	$	-	$	3,985	$	16
U.S. Government agencies		111,662		2,682		56,396		2,890		168,058		5,572
State and political subdivisions		2,921		3		-		-		2,921		3
Other securities		573		1		-		-		573		1
Total	$	119,141	$	2,703	$	56,396	$	2,890	$	175,537	$	5,592
December 31, 2012
Held-to-Maturity
U.S. Government agencies	$	196,783	$	679	$	-	$	-	$	196,783	$	679
State and political subdivisions		13,098		70		511		90		13,609		160
Total	$	209,881	$	749	$	511	$	90	$	210,392	$	839
Available-for-Sale
U.S. Government agencies	$	105,994	$	292	$	-	$	-	$	105,994	$	292
Mortgage-backed securities		14,420		88		25		1		14,445		89
State and political subdivisions		1,229		1		-		-		1,229		1
Other securities		1		4		-		-		1		4
Total	$	121,644	$	385	$	25	$	1	$	121,669	$	386

Investment Income [Table Text Block]

(In thousands)	2013		2012		2011
Taxable
Held-to-maturity	$	3,314	$	3,107	$	4,229
Available-for-sale		2,239		2,214		2,490
Non-taxable
Held-to-maturity		7,682		7,395		7,864
Available-for-sale		65		5		-
Total	$	13,300	$	12,721	$	14,583

Investments Classified by Contractual Maturity Date [Table Text Block]

	Held-to-Maturity				Available-for-Sale
(In thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
One year or less	$	26,340	$	26,405	$	1,982	$	1,984
After one through five years		255,465		252,709		100,306		99,348
After five through ten years		276,958		269,547		95,786		91,249
After ten years		186,925		182,784		895		965
Other securities		-		-		18,248		18,731
Total	$	745,688	$	731,445	$	217,217	$	212,277