3) Securities

The amortized cost and estimated fair value of securities at year-end were as follows:

2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Estimated Fair Value
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	324,077	$	2,457	$	(2,304	)	$	324,230
U.S. Treasury		30,047		—		(44	)		30,003
Trust preferred securities		15,000		132		—			15,132
U.S. Government sponsored entities		9,042		13		(14	)		9,041
Corporate bonds		6,412		261		—			6,673

Total	$	384,578	$	2,863	$	(2,362	)	$	385,079


Securities held-to-maturity:
Municipals — tax exempt	$	93,518	$	1,517	$	(863	)	$	94,172
Agency mortgage-backed securities		15,793		24		(168	)		15,649

Total	$	109,311	$	1,541	$	(1,031	)	$	109,821

2014	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Estimated Fair Value
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	150,570	$	3,867	$	(265	)	$	154,172
Corporate bonds		35,927		959		(23	)		36,863
Trust preferred securities		15,000		300		—			15,300

Total	$	201,497	$	5,126	$	(288	)	$	206,335


Securities held-to-maturity:
Municipals — tax exempt	$	79,882	$	1,011	$	(1,346	)	$	79,547
Agency mortgage-backed securities		15,480		44		(118	)		15,406

Total	$	95,362	$	1,055	$	(1,464	)	$	94,953

Securities with unrealized losses at year end, aggregated by investment category and length of time that individual securities have been in an unrealized loss position, are as follows:

	Less Than 12 Months					12 Months or More					Total
2015	Fair Value		Unrealized (Losses)			Fair Value		Unrealized (Losses)			Fair Value		Unrealized (Losses)
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	241,067	$	(2,258	)	$	2,165	$	(46	)	$	243,232	$	(2,304	)
U.S. Treasury		30,003		(44	)		—		—			30,003		(44	)
U.S. Government sponsored entities		4,980		(14	)		—		—			4,980		(14	)

Total	$	276,050	$	(2,316	)	$	2,165	$	(46	)	$	278,215	$	(2,362	)


Securities held-to-maturity:
Municipals — Tax Exempt	$	9,920	$	(78	)	$	24,412	$	(785	)	$	34,332	$	(863	)
Agency mortgage-backed securities		7,152		(89	)		4,409		(79	)		11,561		(168	)

Total	$	17,072	$	(167	)	$	28,821	$	(864	)	$	45,893	$	(1,031	)

	Less Than 12 Months					12 Months or More					Total
2014	Fair Value		Unrealized (Losses)			Fair Value		Unrealized (Losses)			Fair Value		Unrealized (Losses)
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	12,491	$	(27	)	$	35,614	$	(238	)	$	48,105	$	(265	)
Corporate bonds		—		—			5,148		(23	)		5,148		(23	)

Total	$	12,491	$	(27	)	$	40,762	$	(261	)	$	53,253	$	(288	)


Securities held-to-maturity:
Municipals — Tax Exempt	$	1,884	$	(16	)	$	42,867	$	(1,330	)	$	44,751	$	(1,346	)
Agency mortgage-backed securities		4,869		(29	)		4,974		(89	)		9,843		(118	)

Total	$	6,753	$	(45	)	$	47,841	$	(1,419	)	$	54,594	$	(1,464	)

There were no holdings of securities of any one issuer, other than the U.S. Government and its sponsored entities, in an amount greater than 10% of shareholders' equity. At December 31, 2015, the Company held 460 securities (193 available-for-sale and 267 held-to-maturity), of which 193 had fair values below amortized cost. At December 31, 2015, there were $2,165,000 of agency mortgage-backed securities available-for-sale, $4,409,000 of agency mortgage-backed securities held-to-maturity and $24,412,000 of municipals bonds held-to-maturity carried with an unrealized loss for 12 months or greater. The total unrealized loss for securities 12 months or greater was $910,000 at December 31, 2015. The unrealized losses were due to higher interest rates. The issuers are of high credit quality and all principal amounts are expected to be paid when securities mature. The fair value is expected to recover as the securities approach their maturity date and/or market rates decline. The Company does not believe that it is more likely than not that the Company will be required to sell a security in an unrealized loss position prior to recovery in value. The Company does not consider these securities to be other-than-temporarily impaired at December 31, 2015.

The proceeds from sales of securities and the resulting gains and losses are listed below:

	2015			2014			2013
	(Dollars in thousands)
Proceeds	$	71,832		$	108,603		$	26,944
Gross gains		751			1,008			310
Gross losses		(109	)		(911	)		(272	)

The amortized cost and fair value of debt securities as of December 31, 2015, by contractual maturity, are shown below. The expected maturities will differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately.

	Available-for-sale
	Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
Due after 3 months through one year	$	1,999	$	1,996
Due after one through five years		39,454		39,659
Due after five through ten years		4,048		4,062
Due after ten years		15,000		15,132
Agency mortgage-backed securities		324,077		324,230

Total	$	384,578	$	385,079

	Held-to-maturity
	Amortized Cost		Estimated Fair Value
	(Dollars in thousands)
Due less than 3 months	$	879	$	882
Due after 3 months through one year		1,353		1,362
Due after one through five years		5,554		5,626
Due after five through ten years		13,990		14,608
Due after ten years		71,742		71,694
Agency mortgage-backed securities		15,793		15,649

Total	$	109,311	$	109,821

Securities with amortized cost of $134,235,000 and $147,497,000 as of December 31, 2015 and 2014 were pledged to secure public deposits and for other purposes as required or permitted by law or contract.