MARKETABLE SECURITIES

The following tables summarize the amortized cost and fair value of securities available for sale and securities held to maturity as of September 30, 2018 and December 31, 2017 and the corresponding amounts of gross unrealized gains and losses:



September 30, 2018	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available for sale:
Corporate bonds	$	19,762	$	—	$	648	$	19,114
Municipal securities	15,814		—		451		15,363
Mortgage-backed securities	91,208		—		4,447		86,761
Collateralized mortgage obligations	115,125		—		3,985		111,140
Total available for sale	$	241,909	$	—	$	9,531	$	232,378

Held to maturity:
Municipal securities	$	142,419	$	710	$	2,420	$	140,709
Mortgage-backed securities	17,871		77		611		17,337
Collateralized mortgage obligations	4,549		46		45		4,550
Total held to maturity	$	164,839	$	833	$	3,076	$	162,596



December 31, 2017	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Available for sale:
Corporate bonds	$	18,823	$	64	$	50	$	18,837
Municipal securities	7,746		—		200		7,546
Mortgage-backed securities	92,471		—		1,793		90,678
Collateralized mortgage obligations	116,809		5		1,503		115,311
Total available for sale	$	235,849	$	69	$	3,546	$	232,372

Held to maturity:
Municipal securities	$	146,496	$	2,244	$	218	$	148,522
Mortgage-backed securities	22,026		199		230		21,995
Collateralized mortgage obligations	6,162		111		—		6,273
Total held to maturity	$	174,684	$	2,554	$	448	$	176,790

Management evaluates securities for other-than-temporary impairment (“OTTI”) on at least a quarterly basis, and more frequently when economic or market concerns warrant such evaluation. Consideration is given to (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, and (3) 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. The Company did not record any OTTI losses on any of its securities during the nine months ended September 30, 2018 or for the year ended December 31, 2017.

Information pertaining to securities with gross unrealized losses as of September 30, 2018 and December 31, 2017 aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position is detailed in the following tables:



	Less Than 12 Months					12 Months or Longer					Total
September 30, 2018	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
Available for sale:
Corporate bonds	$	(648	)	$	19,114	$	—		$	—	$	(648	)	$	19,114
Municipal securities	(65		)	7,557		(386		)	7,289		(451		)	14,846
Mortgage-backed securities	(469		)	15,439		(3,978		)	71,322		(4,447		)	86,761
Collateralized mortgage obligations	(2,126		)	68,879		(1,859		)	42,261		(3,985		)	111,140
Total available for sale	$	(3,308	)	$	110,989	$	(6,223	)	$	120,872	$	(9,531	)	$	231,861

Held to maturity:
Municipal securities	$	(1,633	)	$	75,935	$	(787	)	$	20,088	$	(2,420	)	$	96,023
Mortgage-backed securities	(232		)	6,236		(379		)	8,004		(611		)	14,240
Collateralized mortgage obligations	(45		)	2,363		—			—		(45		)	2,363
Total held to maturity	$	(1,910	)	$	84,534	$	(1,166	)	$	28,092	$	(3,076	)	$	112,626



	Less Than 12 Months					12 Months or Longer					Total
December 31, 2017	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
Available for sale:
Corporate bonds	$	(50	)	$	8,019	$	—		$	—	$	(50	)	$	8,019
Municipal securities	—			—		(200		)	7,546		(200		)	7,546
Mortgage-backed securities	(658		)	42,881		(1,135		)	47,797		(1,793		)	90,678
Collateralized mortgage obligations	(1,091		)	93,584		(412		)	21,258		(1,503		)	114,842
Total available for sale	$	(1,799	)	$	144,484	$	(1,747	)	$	76,601	$	(3,546	)	$	221,085

Held to maturity:
Municipal securities	$	(37	)	$	9,230	$	(181	)	$	19,961	$	(218	)	$	29,191
Mortgage-backed securities	(57		)	6,499		(173		)	9,747		(230		)	16,246
Collateralized mortgage obligations	—			—		—			—		—			—
Total held to maturity	$	(94	)	$	15,729	$	(354	)	$	29,708	$	(448	)	$	45,437

The number of investment positions in an unrealized loss position totaled 203 at September 30, 2018. The securities in a loss position were composed of tax-exempt municipal bonds, corporate bonds, collateralized mortgage obligations and mortgage backed securities. Management believes the unrealized loss on the remaining securities is a function of the movement of interest rates since the time of purchase. Based on evaluation of available evidence, including recent changes in interest rates, credit rating information and information obtained from regulatory filings, management believes the declines in fair value for these securities are temporary. Should the impairment of any of these securities become other-than-temporary, the cost basis of the investment would be reduced and the resulting loss recognized in net income in the period the OTTI is identified. The Company does not have the intent to sell these securities and it is likely that it will not be required to sell the securities before their anticipated recovery. The Company does not consider these securities to be OTTI at September 30, 2018.

Mortgage-backed securities and collateralized mortgage obligations are backed by pools of mortgages that are insured or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association or the Government National Mortgage Association.

As of September 30, 2018, there were no holdings of securities of any one issuer, other than the U.S. government and its agencies, in an amount greater than 10% of shareholders’ equity.

Securities with fair values of approximately $233,559 and $245,600 at September 30, 2018 and December 31, 2017, respectively, were pledged to secure public fund deposits and for other purposes as required or permitted by law.

The proceeds from sales of available for sale securities and the associated gains and losses are listed below for:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018			2017
Proceeds from sales	$	102,356		$	199,974	$	111,813		$	214,736
Gross gains	4			—		4			38
Gross losses	(3		)	—		(54		)	(13		)

During the nine months ended September 30, 2017, the Company sold three held-to-maturity municipal securities. The Company sold these municipal securities based upon internal credit analysis, under the belief that they had experienced significant deterioration in creditworthiness. The risk exposure presented by these municipalities had increased beyond acceptable levels, and the Company determined that it was reasonably possible that all amounts due would not be collected. The credit analysis determined that the municipalities had been significantly impacted because their tax bases are heavily reliant on the energy industry relative to other sectors of the economy. Specifically, the revenues of these municipalities have been adversely impacted by the significant decline in energy prices since 2014. The Company believes the sale of these securities were merited and permissible under the applicable accounting guidelines because of the significant deterioration in the creditworthiness of the issuers.

There were no held to maturity securities sold during the three or nine months ended September 30, 2018. Sale of securities held to maturity were as follows for:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2017		2017
Proceeds from sales	$	—	$	923
Amortized cost	—		907
Gross realized gains	—		16
Tax expense related to securities gains/losses	—		(4		)

The contractual maturities at September 30, 2018 of available for sale and held to maturity securities at carrying value and estimated fair value are shown below. The Company invests in mortgage-backed securities and collateralized mortgage obligations that have expected maturities that differ from their contractual maturities. These differences arise because borrowers and/or issuers may have the right to call or prepay their obligation with or without call or prepayment penalties.



	Available for Sale				Held to Maturity
September 30, 2018	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due within one year	$	—	$	—	$	769	$	768
Due after one year through five years	11,234		10,926		19,153		19,244
Due after five years through ten years	16,668		16,262		42,448		42,774
Due after ten years	7,674		7,289		80,049		77,923
Mortgage-backed securities	91,208		86,761		17,871		17,337
Collateralized mortgage obligations	115,125		111,140		4,549		4,550
Total Securities	$	241,909	$	232,378	$	164,839	$	162,596