(3)	SECURITIES

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

	September 30, 2015		December 31, 2014
	(Dollars in thousands)
Held for investment, at cost (fair value: $8,398 and $8,671, respectively)	$	8,333	$	8,593
Available for sale, at fair value		499,525		516,190
Total	$	507,858	$	524,783

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
September 30, 2015	(Dollars in thousands)
Mortgage backed securities (1)	$	382	$	30	$	—	$	412
States and political subdivisions		7,951		35		—		7,986
Total	$	8,333	$	65	$	—	$	8,398
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

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
September 30, 2015	(Dollars in thousands)
U.S. treasuries	$	279,331	$	1,966	$	—		$	281,297
U.S. federal agencies		133,670		870		(54	)		134,486
Mortgage backed securities (1)		22,587		500		(557	)		22,530
States and political subdivisions		49,815		1,552		(41	)		51,326
Other securities (2)		9,887		197		(198	)		9,886
Total	$	495,290	$	5,085	$	(850	)	$	499,525
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

(1)

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

(2)

Primarily consists of equity securities.

The unrealized gains decreased in 2015 primarily due to the reclassification of an unrealized gain on one investment of $3.3 million from other comprehensive income to a realized gain by Council Oak Partners, LLC, a wholly-owned subsidiary of the Company. The realized gain is reported as securities transactions within the noninterest income section of the consolidated statement of comprehensive income.

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.

	September 30, 2015				December 31, 2014
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
Held for Investment
Contractual maturity of debt securities:
Within one year	$	4,978	$	4,985	$	1,451	$	1,456
After one year but within five years		3,003		3,031		6,603		6,642
After five years but within ten years		316		343		380		396
After ten years		36		39		159		177
Total	$	8,333	$	8,398	$	8,593	$	8,671
Available for Sale
Contractual maturity of debt securities:
Within one year	$	132,557	$	132,794	$	41,772	$	41,870
After one year but within five years		266,217		269,077		350,975		352,044
After five years but within ten years		12,493		13,068		21,990		22,717
After ten years		77,590		78,155		87,252		88,132
Total debt securities		488,857		493,094		501,989		504,763
Equity securities		6,433		6,431		7,364		11,427
Total	$	495,290	$	499,525	$	509,353	$	516,190

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:

	September 30, 2015		December 31, 2014
	(Dollars in thousands)
Book value of pledged securities	$	450,473	$	522,190