(4) SECURITIES

The following table summarizes securities held for investment and securities available for sale:

	December 31,
	2014		2013
	(Dollars in thousands)
Held for investment at cost (fair value: $8,671 and $12,094, respectively)	$	8,593	$	11,986
Available for sale, at fair value		516,190		515,641
Total	$	524,783	$	527,627

The following table summarizes the amortized cost and estimated fair values of securities held for investment:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(Dollars in thousands)
December 31, 2014
Mortgage backed securities (1)	$	471	$	34	$	—		$	505
States and political subdivisions		8,122		44		—			8,166
Total	$	8,593	$	78	$	—		$	8,671
December 31, 2013
Mortgage backed securities (1)	$	607	$	48	$	—		$	655
States and political subdivisions		11,379		67		(7	)		11,439
Total	$	11,986	$	115	$	(7	)	$	12,094

The following table summarizes the amortized cost and estimated fair values of securities available for sale:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(Dollars in thousands)
December 31, 2014
U.S. treasuries	$	248,767	$	404	$	(178	)	$	248,993
U.S. federal agencies		171,641		983		(175	)		172,449
Mortgage backed securities (1)		26,441		602		(586	)		26,457
States and political subdivisions		51,706		1,716		(49	)		53,373
Other securities (2)		10,798		4,252		(132	)		14,918
Total	$	509,353	$	7,957	$	(1,120	)	$	516,190
December 31, 2013
U.S. treasuries	$	29,946	$	—	$	(85	)	$	29,861
U.S. federal agencies		386,391		1,399		(505	)		387,285
Mortgage backed securities (1)		32,057		625		(4	)		32,678
States and political subdivisions		49,116		1,290		(72	)		50,334
Other securities (2)		12,121		3,503		(141	)		15,483
Total	$	509,631	$	6,817	$	(807	)	$	515,641

(1)	Primarily consists of FHLMC, FNMA, GNMA and mortgage backed securities through U.S. agencies.

(2)	Primarily consists of equity securities.

The maturities of securities held for investment and available for sale are summarized in the following table using contractual maturities. Actual maturities may differ from contractual maturities due to obligations that are called or prepaid. For purposes of the maturity table, mortgage-backed securities, which are not due at a single maturity date, have been presented at their contractual maturity.

	December 31,
	2014				2013
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
Held for Investment
Contractual maturity of debt securities:
Within one year	$	1,451	$	1,456	$	3,640	$	3,649
After one year but within five years		6,603		6,642		7,277		7,321
After five years but within ten years		380		396		837		865
After ten years		159		177		232		259
Total	$	8,593	$	8,671	$	11,986	$	12,094
Available for Sale
Contractual maturity of debt securities:
Within one year	$	41,772	$	41,870	$	208,625	$	209,065
After one year but within five years		350,975		352,044		167,554		168,210
After five years but within ten years		21,990		22,717		27,195		27,797
After ten years		87,252		88,132		97,542		98,551
Total debt securities		501,989		504,763		500,916		503,623
Equity securities		7,364		11,427		8,715		12,018
Total	$	509,353	$	516,190	$	509,631	$	515,641

The following is a detail of proceeds from sales and realized securities gains and losses, on available for sale securities:

	Year Ended December 31,
	2014		2013		2012
	(Dollars in thousands)
Proceeds	$	4,855	$	521	$	6,025
Gross gains realized		1,641		456		5,575
Gross losses realized		—		36		660

The following table is a summary of the Company’s book value of securities that were pledged as collateral for public funds on deposit, repurchase agreements and for other purposes as required or permitted by law:

	Year Ended December 31,
	2014		2013
	(Dollars in thousands)
Book value of pledged securities	$	522,190	$	443,835

The following table summarizes securities with unrealized losses, segregated by the duration of the unrealized loss, at December 31, 2014 and 2013 respectively:

	Less than 12 Months				More than 12 Months				Total
	Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses		Estimated Fair Value		Unrealized Losses
	(Dollars in thousands)
December 31, 2014
Held for Investment
Mortgage backed securities	$	—	$	—	$	—	$	—	$	—	$	—
States and political subdivisions		—		—		—		—		—		—
Total	$	—	$	—	$	—	$	—	$	—	$	—
Available for Sale
U.S. treasuries	$	149,589	$	178	$	—	$	—	$	149,589	$	178
U.S. federal agencies		40,551		113		13,653		62		54,204		175
Mortgage backed securities		17,041		585		26		1		17,067		586
States and political subdivisions		3,093		26		977		23		4,070		49
Other securities		—		—		300		132		300		132
Total	$	210,274	$	902	$	14,956	$	218	$	225,230	$	1,120
December 31, 2013
Held for Investment
Mortgage backed securities	$	1	$	—	$	1	$	—	$	2	$	—
States and political subdivisions		—		—		1,328		7		1,328		7
Total	$	1	$	—	$	1,329	$	7	$	1,330	$	7
Available for Sale
U.S. treasuries	$	29,861	$	85	$	—	$	—	$	29,861	$	85
U.S. federal agencies		79,411		246		150,188		259		229,599		505
Mortgage backed securities		66		4		—		—		66		4
States and political subdivisions		2,459		72		—		—		2,459		72
Other securities		160		141		—		—		160		141
Total	$	111,957	$	548	$	150,188	$	259	$	262,145	$	807

Declines in the fair value of held for investment 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 for investment until they mature, at which time the Company will receive full value for the securities. Furthermore, as of December 31, 2014 and 2013, the Company 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 debt securities were purchased. The fair value is expected to recover as the securities 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, and has no intent or requirement to sell before the recovery of the unrealized loss; therefore, the Company has not recognized any impairment in the Company’s consolidated statement of comprehensive income.