5.	Investment Securities

At June 30, 2015 and 2014 and at December 31, 2014, the Company classified all of its investment securities portfolio as AFS. Accordingly, investment securities are stated at estimated fair value in the consolidated financial statements with unrealized gains and losses, net of related income tax, reported as a separate component of stockholders’ equity and included in accumulated other comprehensive income (loss).

The following table presents the amortized cost and estimated fair value of investment securities AFS as of the dates indicated. The Company’s investment in the “CRA qualified investment fund” includes shares held in a mutual fund that qualifies under the Community Reinvestment Act of 1977 for community reinvestment purposes. The Company’s holdings of equity securities in Federal Home Loan Bank of Dallas (“FHLB”) and First National Banker’s Bankshares, Inc. (“FNBB”) do not have readily determinable fair values and are carried at cost.


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(Dollars in thousands)
June 30, 2015:
Obligations of state and political subdivisions	$	496,777	$	11,768	$	(1,630	)	$	506,915
U.S. Government agency securities		257,849		4,627		(1,723	)		260,753
Corporate obligations		3,574		0		0			3,574
CRA qualified investment fund		1,028		0		(8	)		1,020
FHLB and FNBB equity securities		10,015		0		0			10,015

Total	$	769,243	$	16,395	$	(3,361	)	$	782,277


December 31, 2014:
Obligations of state and political subdivisions	$	555,335	$	18,267	$	(393	)	$	573,209
U.S. Government agency securities		245,854		6,144		(765	)		251,233
Corporate obligations		654		0		0			654
FHLB and FNBB equity securities		14,225		0		0			14,225

Total	$	816,068	$	24,411	$	(1,158	)	$	839,321


June 30, 2014:
Obligations of state and political subdivisions	$	603,533	$	15,536	$	(2,504	)	$	616,565
U.S. Government agency securities		254,878		5,613		(2,180	)		258,311
Corporate obligations		685		0		0			685
FHLB and FNBB equity securities		16,568		0		0			16,568

Total	$	875,664	$	21,149	$	(4,684	)	$	892,129

The following table shows estimated fair value of investment securities AFS having gross unrealized losses and the amount of such unrealized losses, aggregated by investment category and length of time that individual investment securities have been in a continuous unrealized loss position, as of the dates indicated.


	Less than 12 Months				12 Months or More				Total
	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
	(Dollars in thousands)
June 30, 2015:
Obligations of state and political subdivisions	$	104,621	$	1,532	$	7,515	$	98	$	112,136	$	1,630
U.S. Government agency securities		76,252		1,534		7,181		189		83,433		1,723
CRA qualified investment fund		1,020		8		0		0		1,020		8

Total temporarily impaired securities	$	181,893	$	3,074	$	14,696	$	287	$	196,589	$	3,361


December 31, 2014:
Obligations of state and political subdivisions	$	29,174	$	75	$	34,414	$	318	$	63,588	$	393
U.S. Government agency securities		9,630		25		47,626		740		57,256		765

Total temporarily impaired securities	$	38,804	$	100	$	82,040	$	1,058	$	120,844	$	1,158


June 30, 2014:
Obligations of state and political subdivisions	$	60,769	$	386	$	79,000	$	2,118	$	139,769	$	2,504
U.S. Government agency securities		15,227		67		58,608		2,113		73,835		2,180

Total temporarily impaired securities	$	75,996	$	453	$	137,608	$	4,231	$	213,604	$	4,684

In evaluating the Company’s unrealized loss positions for other-than-temporary impairment of its investment securities portfolio, management considers the credit quality of the issuer, the nature and cause of the unrealized loss, the severity and duration of the impairments and other factors. At June 30, 2015 management determined the unrealized losses were the result of fluctuations in interest rates and did not reflect deteriorations of the credit quality of the investments. Accordingly, management considers these unrealized losses to be temporary in nature. The Company does not have the intent to sell these investment securities with unrealized losses and, more likely than not, will not be required to sell these investment securities before fair value recovers to amortized cost.

The following table shows the amortized cost and estimated fair value of investment securities AFS by maturity or estimated date of repayment as of the date indicated.


	June 30, 2015
Maturity or Estimated Repayment	Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
One year or less	$	36,133	$	36,619
After one year to five years		139,079		140,690
After five years to ten years		189,702		192,251
After ten years		404,329		412,717

Total	$	769,243	$	782,277

For purposes of this maturity distribution, all investment securities AFS are shown based on their contractual maturity date or estimated date of repayment, except (i) FHLB and FNBB equity securities and the CRA qualified investment fund with no contractual maturity date are shown in the longest maturity category and (ii) U.S. Government agency securities and municipal housing authority securities backed by residential mortgages are allocated among various maturities based on an estimated repayment schedule utilizing Bloomberg median prepayment speeds or other estimates of prepayment speeds and interest rate levels at the measurement date. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

The following table is a summary of sales activities in the Company’s investment securities AFS for the periods indicated.


	Three Months Ended June 30,				Six Months Ended June 30,
	2015		2014		2015			2014
	(Dollars in thousands)
Sales proceeds	$	2,660	$	47,170	$	32,777		$	48,394


Gross realized gains	$	85	$	18	$	2,619		$	23
Gross realized losses		0		0		(1	)		0

Net gains on investment securities	$	85	$	18	$	2,618		$	23