Note 3 - Investment Securities

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

NOTE 3: INVESTMENT SECURITIES

The amortized cost and fair value of investment securities that are classified as held-to-maturity and available-for-sale are as follows:

	Years Ended December 31
	2015									2014
(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	$	237,139	$	582	$	(1,395	)	$	236,326	$	418,914	$	929	$	(4,055	)	$	415,788
Mortgage-backed securities		24,774		86		(290	)		24,570		29,743		56		(411	)		29,388
State and political subdivisions		440,676		9,138		(123	)		449,691		328,310		7,000		(573	)		334,737
Other securities		2,784		--		--			2,784		620		--		--			620
Total	$	705,373	$	9,806	$	(1,808	)	$	713,371	$	777,587	$	7,985	$	(5,039	)	$	780,533
Available-for-Sale
U.S. Treasury	$	4,000	$	--	$	(6	)	$	3,994	$	4,000	$	1	$	(9	)	$	3,992
U.S. Government agencies		121,017		118		(898	)		120,237		275,381		15		(2,580	)		272,816
Mortgage-backed securities		650,619		937		(4,130	)		647,426		1,579		--		(7	)		1,572
State and political subdivisions		9,762		112		--			9,874		6,536		7		(3	)		6,540
Other securities		40,394		420		(938	)		39,876		19,985		386		(8	)		20,363
Total	$	825,792	$	1,587	$	(5,972	)	$	821,407	$	307,481	$	409	$	(2,607	)	$	305,283

Securities with limited marketability, such as stock in the Federal Reserve Bank and the Federal Home Loan Bank, are carried at cost and are reported as other available-for-sale securities in the table above.

Certain investment securities are valued at less than their historical cost.  Total fair value of these investments at December 31, 2015 and 2014, was $872.4 million and $680.5 million, which is approximately 57.1% and 62.8%, respectively, of the Company’s combined available-for-sale and held-to-maturity investment portfolios.

The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31:

	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, 2015
Held-to-Maturity
U.S. Government agencies	$	107,758	$	567	$	79,166	$	828	$	186,924	$	1,395
Mortgage-backed securities		7,958		94		8,144		196		16,102		290
State and political subdivisions		27,866		100		3,946		23		31,812		123
Total	$	143,582	$	761	$	91,256	$	1,047	$	234,838	$	1,808
Available-for-Sale
U.S. Treasury	$	3,994	$	6	$	--	$	--	$	3,994	$	6
U.S. Government agencies		62,473		317		46,023		581		108,496		898
Mortgage-backed securities		523,185		4,130		--		--		523,185		4,130
State and political subdivisions		281		--		--		--		281		--
Other securities		1,060		937		510		1		1,570		938
Total	$	590,993	$	5,390	$	46,533	$	582	$	637,526	$	5,972
December 31, 2014
Held-to-Maturity
U.S. Government agencies	$	265,591	$	2,500	$	84,398	$	1,555	$	349,989	$	4,055
Mortgage-backed securities		10,077		67		14,250		344		24,327		411
State and political subdivisions		57,607		444		8,976		129		66,583		573
Total	$	333,275	$	3,011	$	107,624	$	2,028	$	440,899	$	5,039
Available-for-Sale
U.S. Treasury	$	3,992	$	9	$	--	$	--	$	3,992	$	9
U.S. Government agencies		171,114		1,472		61,195		1,108		232,309		2,580
Mortgage-backed securities		1,542		7		--		--		1,542		7
State and political subdivisions		1,005		3		--		--		1,005		3
Other securities		764		8		--		--		764		8
Total	$	178,417	$	1,499	$	61,195	$	1,108	$	239,612	$	2,607

These declines primarily resulted from the rate for these investments yielding less than current market rates.  Based on evaluation of available evidence, management believes the declines in fair value for these securities are temporary. Management does not have the intent to sell these securities and management believes it is more likely than not the Company will not have to sell these securities before recovery of their amortized cost basis less any current period credit losses.

Declines in the fair value of held-to-maturity and available-for-sale securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses.  In estimating other-than-temporary impairment losses, management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer, and (iii) the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value. 

Management has the ability and intent to hold the securities classified as held to maturity until they mature, at which time the Company expects to receive full value for the securities.  Furthermore, as of December 31, 2015, management also had the ability and intent to hold the securities classified as available-for-sale for a period of time sufficient for a recovery of cost.  The unrealized losses are largely due to increases in market interest rates over the yields available at the time the underlying securities were purchased.  The fair value is expected to recover as the bonds approach their maturity date or repricing date or if market yields for such investments decline.  Management does not believe any of the securities are impaired due to reasons of credit quality.  Accordingly, as of December 31, 2015, management believes the impairments detailed in the table above are temporary.  Should the impairment of any of these securities become other than temporary, the cost basis of the investment will be reduced and the resulting loss recognized in net income in the period the other-than-temporary impairment is identified.

Income earned on the above securities for the years ended December 31, 2015, 2014 and 2013, is as follows:

(In thousands)	2015		2014		2013
Taxable
Held-to-maturity	$	5,162	$	5,839	$	3,314
Available-for-sale		12,129		2,785		2,239
Non-taxable
Held-to-maturity		11,635		10,625		7,682
Available-for-sale		1,687		108		65
Total	$	30,613	$	19,357	$	13,300

The amortized cost and estimated fair value by maturity of securities are shown in the following table.  Securities are classified according to their contractual maturities without consideration of principal amortization, potential prepayments or call options.  Accordingly, actual maturities may differ from contractual maturities.

	Held-to-Maturity				Available-for-Sale
(In thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair   Value
One year or less	$	28,739	$	28,807	$	28,543	$	28,512
After one through five years		315,065		314,557		88,911		88,048
After five through ten years		127,795		130,087		13,727		13,899
After ten years		209,000		215,350		5,363		5,412
Securities not due on a single maturity date		24,774		24,570		650,619		647,426
Other securities (no maturity)		--		--		38,629		38,110
Total	$	705,373	$	713,371	$	825,792	$	821,407

The carrying value, which approximates the fair value, of securities pledged as collateral, to secure public deposits and for other purposes, amounted to $840.4 million at December 31, 2015 and $520.4 million at December 31, 2014. The book value of securities sold under agreements to repurchase amounted to $96.8 million and $100.8 million for December 31, 2015 and 2014, respectively.

There were $350,000 of gross realized gains and $43,000 of realized losses from the sale of available for sale securities during the year ended December 31, 2015. There were $199,000 of gross realized gains and $191,000 of realized losses from the sale of available for sale securities during the year ended December 31, 2014. There were $151,000 of gross realized gains and $302,000 of realized losses from the sale of available for sale securities during the year ended December 31, 2013. As part of its strategy related to the 2012 acquisitions, the Company liquidated the acquired mortgage-backed securities, resulting in $193,000 of net realized losses during 2013. The income tax expense/benefit related to security gains/losses was 39.225% of the gross amounts.

The state and political subdivision debt obligations are primarily non-rated bonds and represent small, Arkansas, Illinois, Kansas, Missouri, Tennessee and Texas issues, which are evaluated on an ongoing basis.