(3.) INVESTMENT SECURITIES

The amortized cost and estimated fair value of investment securities are summarized below (in thousands).


		Amortized		Unrealized		Unrealized		Fair
		Cost		Gains		Losses		Value
December 31, 2017
Securities available for sale:
U.S. Government agencies and government
sponsored enterprises	$	163,025	$	122	$	1,258	$	161,889
Mortgage-backed securities:
Federal National Mortgage Association		311,830		313		3,220		308,923
Federal Home Loan Mortgage Corporation		41,290		76		675		40,691
Government National Mortgage Association		12,051		193		12		12,232
Collateralized mortgage obligations:
Federal National Mortgage Association		217		1		1		217
Federal Home Loan Mortgage Corporation		45		-		-		45
Privately issued		-		976		-		976
Total mortgage-backed securities		365,433		1,559		3,908		363,084
Total available for sale securities	$	528,458	$	1,681	$	5,166	$	524,973
Securities held to maturity:
State and political subdivisions		283,557		2,317		662		285,212
Mortgage-backed securities:
Federal National Mortgage Association		9,732		16		88		9,660
Federal Home Loan Mortgage Corporation		3,213		-		119		3,094
Government National Mortgage Association		26,841		-		330		26,511
Collateralized mortgage obligations:
Federal National Mortgage Association		76,432		-		1,958		74,474
Federal Home Loan Mortgage Corporation		93,810		3		2,165		91,648
Government National Mortgage Association		22,881		5		502		22,384
Total mortgage-backed securities		232,909		24		5,162		227,771
Total held to maturity securities	$	516,466	$	2,341	$	5,824	$	512,983


December 31, 2016
Securities available for sale:
U.S. Government agencies and government
sponsored enterprises	$	187,325	$	512	$	1,569	$	186,268
Mortgage-backed securities:
Federal National Mortgage Association		288,949		897		4,413		285,433
Federal Home Loan Mortgage Corporation		30,182		114		807		29,489
Government National Mortgage Association		15,473		316		15		15,774
Collateralized mortgage obligations:
Federal National Mortgage Association		16,921		74		125		16,870
Federal Home Loan Mortgage Corporation		5,142		-		65		5,077
Privately issued		-		824		-		824
Total mortgage-backed securities		356,667		2,225		5,425		353,467
Asset-backed securities		-		191		-		191
Total available for sale securities	$	543,992	$	2,928	$	6,994	$	539,926

		Amortized		Unrealized		Unrealized		Fair
		Cost		Gains		Losses		Value
December 31, 2016 (continued)
Securities held to maturity:
State and political subdivisions		305,248		2,127		1,616		305,759
Mortgage-backed securities:
Federal National Mortgage Association		10,362		1		124		10,239
Federal Home Loan Mortgage Corporation		3,290		-		150		3,140
Government National Mortgage Association		24,575		18		182		24,411
Collateralized mortgage obligations:
Federal National Mortgage Association		83,929		21		1,573		82,377
Federal Home Loan Mortgage Corporation		101,025		80		1,827		99,278
Government National Mortgage Association		14,909		40		162		14,787
Total mortgage-backed securities		238,090		160		4,018		234,232
Total held to maturity securities	$	543,338	$	2,287	$	5,634	$	539,991

Investment securities with a total fair value of $838.4 million and $907.7 million at December 31, 2017 and 2016, respectively, were pledged as collateral to secure public deposits and for other purposes required or permitted by law.

Interest and dividends on securities for the years ended December 31 are summarized as follows (in thousands):


		2017		2016		2015
Taxable interest and dividends	$	17,886	$	17,025	$	16,123
Tax-exempt interest and dividends		5,869		5,892		5,752
Total interest and dividends on securities	$	23,755	$	22,917	$	21,875

Sales and calls of securities available for sale for the years ended December 31 were as follows (in thousands):


		2017		2016		2015
Proceeds from sales	$	50,084	$	95,261	$	54,277
Gross realized gains		1,266		2,695		2,000
Gross realized losses		6		-		12

The scheduled maturities of securities available for sale and securities held to maturity at December 31, 2017 are shown below. Actual expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations (in


		Amortized		Fair
		Cost		Value
Debt securities available for sale:
Due in one year or less	$	2	$	2
Due from one to five years		123,010		122,228
Due after five years through ten years		294,812		292,544
Due after ten years		110,634		110,199
	$	528,458	$	524,973
Debt securities held to maturity:
Due in one year or less	$	57,692	$	57,757
Due from one to five years		159,758		161,514
Due after five years through ten years		103,593		102,507
Due after ten years		195,423		191,205
	$	516,466	$	512,983

Unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of December 31 are summarized as follows (in thousands):


		Less than 12 months				12 months or longer				Total
		Fair		Unrealized		Fair	Unrealized			Fair	Unrealized
		Value		Losses		Value		Losses		Value		Losses
December 31, 2017
Securities available for sale:
U.S. Government agencies and government
sponsored enterprises	$	95,046	$	571	$	31,561	$	687	$	126,607	$	1,258
Mortgage-backed securities:
Federal National Mortgage Association		201,754		1,855		67,383		1,365		269,137		3,220
Federal Home Loan Mortgage Corporation		20,446		192		15,601		483		36,047		675
Government National Mortgage Association		2,432		-		880		12		3,312		12
Collateralized mortgage obligations:
Federal National Mortgage Association		-		-		119		1		119		1
Federal Home Loan Mortgage Corporation		-		-		8		-		8		-
Total mortgage-backed securities		224,632		2,047		83,991		1,861		308,623		3,908
Total available for sale securities		319,678		2,618		115,552		2,548		435,230		5,166
Securities held to maturity:
State and political subdivisions		36,368		295		14,492		367		50,860		662
Mortgage-backed securities:
Federal National Mortgage Association		3,766		29		2,694		59		6,460		88
Federal Home Loan Mortgage Corporation		-		-		3,094		119		3,094		119
Government National Mortgage Association		17,327		136		9,184		194		26,511		330
Collateralized mortgage obligations:
Federal National Mortgage Association		16,830		202		57,645		1,756		74,475		1,958
Federal Home Loan Mortgage Corporation		23,727		337		66,467		1,828		90,194		2,165
Government National Mortgage Association		15,401		340		5,635		162		21,036		502
Total mortgage-backed securities		77,051		1,044		144,719		4,118		221,770		5,162
Total held to maturity securities		113,419		1,339		159,211		4,485		272,630		5,824
Total temporarily impaired securities	$	433,097	$	3,957	$	274,763	$	7,033	$	707,860	$	10,990

	Less than 12 months				12 months or longer				Total
		Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
		Value		Losses		Value		Losses		Value		Losses
December 31, 2016
Securities available for sale:
U.S. Government agencies and government
sponsored enterprises	$	113,261	$	1,566	$	1,458	$	3	$	114,719	$	1,569
Mortgage-backed securities:
Federal National Mortgage Association		211,491		4,413		-		-		211,491		4,413
Federal Home Loan Mortgage Corporation		24,360		807		-		-		24,360		807
Government National Mortgage Association		1,111		15		-		-		1,111		15
Collateralized mortgage obligations:
Federal National Mortgage Association		8,119		125		-		-		8,119		125
Federal Home Loan Mortgage Corporation		5,077		65		-		-		5,077		65
Total mortgage-backed securities		250,158		5,425		-		-		250,158		5,425
Total available for sale securities		363,419		6,991		1,458		3		364,877		6,994
Securities held to maturity:
State and political subdivisions		82,644		1,616		-		-		82,644		1,616
Mortgage-backed securities:
Federal National Mortgage Association		9,253		124		-		-		9,253		124
Federal Home Loan Mortgage Corporation		3,141		150		-		-		3,141		150
Government National Mortgage Association		10,736		182		-		-		10,736		182
Collateralized mortgage obligations:
Federal National Mortgage Association		72,734		1,560		3,107		13		75,841		1,573
Federal Home Loan Mortgage Corporation		92,256		1,825		430		2		92,686		1,827
Government National Mortgage Association		8,675		161		531		1		9,206		162
Total mortgage-backed securities		196,795		4,002		4,068		16		200,863		4,018
Total held to maturity securities		279,439		5,618		4,068		16		283,507		5,634
Total temporarily impaired securities	$	642,858	$	12,609	$	5,526	$	19	$	648,384	$	12,628

The total number of security positions in the investment portfolio in an unrealized loss position at December 31, 2017 was 411 compared to 463 at December 31, 2016. At December 31, 2017, the Company had positions in 172 investment securities with a fair value of $274.8 million and a total unrealized loss of $7.0 million that have been in a continuous unrealized loss position for more than 12 months. At December 31, 2017, there were a total of 239 securities positions in the Company's investment portfolio with a fair value of $433.1 million and a total unrealized loss of $4.0 million that had been in a continuous unrealized loss position for less than 12 months. At December 31, 2016, the Company had positions in nine investment securities with a fair value of $5.5 million and a total unrealized loss of $19 thousand that have been in a continuous unrealized loss position for more than 12 months. At December 31, 2016, there were a total of 454 securities positions in the Company's investment portfolio with a fair value of $642.9 million and a total unrealized loss of $12.6 million that had been in a continuous unrealized loss position for less than 12 months. The unrealized loss on investment securities was predominantly caused by changes in market interest rates subsequent to purchase. The fair value of most of the investment securities in the Company's portfolio fluctuates as market interest rates change.

The Company reviews investment securities on an ongoing basis for the presence of other than temporary impairment ("OTTI") with formal reviews performed quarterly. When evaluating debt securities for OTTI, management considers many factors, including: (1) the length of time and the extent to which the fair value has been less than cost, (2) the financial condition and near-term prospects of the issuer, (3) whether the market decline was affected by macroeconomic conditions, and (4) whether the Company has the intention to sell the debt security or whether it is more likely than not that it will be required to sell the debt security before its anticipated recovery. The assessment of whether OTTI exists involves a high degree of subjectivity and judgment and is based on the information available to management. No impairment was recorded during the years ended December 31, 2017, 2016 and 2015.

Based on management's review and evaluation of the Company's debt securities as of December 31, 2017, the debt securities with unrealized losses were not considered to be OTTI. As of December 31, 2017, the Company does not have the intent to sell any of the securities in a loss position and believes that it is not likely that it will be required to sell any such securities before the anticipated recovery of amortized cost. Accordingly, as of December 31, 2017, management has concluded that unrealized losses on its investment securities are temporary and no further impairment loss has been realized in the Company's consolidated statements of income.