4) Securities

The amortized cost and estimated fair value of securities at September 30, 2017 and December 31, 2016 were as follows:


			Gross		Gross		Estimated
	Amortized		Unrealized		Unrealized		Fair
September 30, 2017	Cost		Gains		(Losses)		Value
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	374,057		1,275		(2,165)	$	373,167
Trust preferred securities		15,000		1,940		—		16,940
Total	$	389,057	$	3,215	$	(2,165)	$	390,107

Securities held-to-maturity:
Agency mortgage-backed securities	$	290,418	$	259	$	(2,341)	$	288,336
Municipals - exempt from Federal tax		89,132		1,054		(677)		89,509
Total	$	379,550	$	1,313	$	(3,018)	$	377,845


			Gross		Gross		Estimated
	Amortized		Unrealized		Unrealized		Fair
December 31, 2016	Cost		Gains		(Losses)		Value
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	293,598	$	928	$	(3,537)	$	290,989
Trust preferred securities		15,000		600		—		15,600
Total	$	308,598	$	1,528	$	(3,537)	$	306,589

Securities held-to-maturity:
Agency mortgage-backed securities	$	233,409	$	15	$	(3,554)	$	229,870
Municipals - exempt from Federal tax		90,601		521		(2,244)		88,878
Total	$	324,010	$	536	$	(5,798)	$	318,748

Securities with unrealized losses at September 30, 2017 and December 31, 2016, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position are as follows:


	Less Than 12 Months				12 Months or More				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
September 30, 2017	Value		(Losses)		Value		(Losses)		Value		(Losses)
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	237,933	$	(2,049)	$	9,346	$	(116)	$	247,279	$	(2,165)
Total	$	237,933	$	(2,049)	$	9,346	$	(116)	$	247,279	$	(2,165)

Securities held-to-maturity:
Agency mortgage-backed securities	$	191,603	$	(1,980)	$	26,547	$	(361)	$	218,150	$	(2,341)
Municipals - exempt from Federal tax		15,922		(116)		20,443		(561)		36,365		(677)
Total	$	207,525	$	(2,096)	$	46,990	$	(922)	$	254,515	$	(3,018)


	Less Than 12 Months				12 Months or More				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
December 31, 2016	Value		(Losses)		Value		(Losses)		Value		(Losses)
	(Dollars in thousands)
Securities available-for-sale:
Agency mortgage-backed securities	$	245,045	$	(3,537)	$	—	$	—	$	245,045	$	(3,537)
Total	$	245,045	$	(3,537)	$	—	$	—	$	245,045	$	(3,537)

Securities held-to-maturity:
Agency mortgage-backed securities	$	222,132	$	(3,528)	$	612	$	(26)	$	222,744	$	(3,554)
Municipals - exempt from Federal tax		57,304		(2,026)		2,046		(218)		59,350		(2,244)
Total	$	279,436	$	(5,554)	$	2,658	$	(244)	$	282,094	$	(5,798)

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 September 30, 2017, the Company held 494 securities (174 available-for-sale and 320 held‑to‑maturity), of which 250 had fair values below amortized cost. At September 30, 2017, there were $9,346,000 of agency mortgage-back securities available-for-sale, $26,547,000 of agency mortgage-backed securities held-to-maturity and $20,443,000 of municipal bonds held-to-maturity, carried with an unrealized loss for 12 months or more. The total unrealized loss for securities 12 months or more was $1,038,000 at September 30, 2017. 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 September 30, 2017.

The proceeds from sales of securities and the resulting gains and losses were as follows for the periods indicated:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
	(Dollars in thousands)				(Dollars in thousands)
Proceeds	$	—	$	—	$	6,536	$	49,171
Gross gains		—		—		—		544
Gross losses		—		—		(6)		(17)

The amortized cost and estimated fair values of securities as of September 30, 2017 are shown by contractual maturity below. The expected maturities will differ from contractual maturities if borrowers have the right to call or pre‑pay obligations with or without call or pre‑payment penalties. Securities not due at a single maturity date are shown separately.


	Available-for-sale
	Amortized		Estimated
	Cost		Fair Value
	(Dollars in thousands)
Due after ten years	$	15,000	$	16,940
Agency mortgage-backed securities		374,057		373,167
Total	$	389,057	$	390,107


	Held-to-maturity
	Amortized		Estimated
	Cost		Fair Value
	(Dollars in thousands)
Due 3 months or less	$	370	$	371
Due after 3 months through one year		505		506
Due after one through five years		3,680		3,756
Due after five through ten years		20,125		20,668
Due after ten years		64,452		64,208
Agency mortgage-backed securities		290,418		288,336
Total	$	379,550	$	377,845