Investment Securities Available-For-Sale

The following table shows investment securities available-for-sale.



(Dollars in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
June 30, 2017
U.S. Treasury and Federal agencies securities	$	430,782	$	725	$	(2,610	)	$	428,897
U.S. States and political subdivisions securities	127,214		1,559		(489		)	128,284
Mortgage-backed securities — Federal agencies	255,747		2,110		(2,159		)	255,698
Corporate debt securities	31,621		64		(159		)	31,526
Foreign government and other securities	300		2		—			302
Total debt securities	845,664		4,460		(5,417		)	844,707
Marketable equity securities	749		4,859		(1		)	5,607
Total investment securities available-for-sale	$	846,413	$	9,319	$	(5,418	)	$	850,314

December 31, 2016
U.S. Treasury and Federal agencies securities	$	424,495	$	809	$	(4,471	)	$	420,833
U.S. States and political subdivisions securities	133,509		1,036		(1,570		)	132,975
Mortgage-backed securities — Federal agencies	252,981		2,175		(2,582		)	252,574
Corporate debt securities	35,266		111		(301		)	35,076
Foreign government and other securities	800		7		—			807
Total debt securities	847,051		4,138		(8,924		)	842,265
Marketable equity securities	1,265		7,007		(70		)	8,202
Total investment securities available-for-sale	$	848,316	$	11,145	$	(8,994	)	$	850,467

At June 30, 2017 and December 31, 2016, the residential mortgage-backed securities held by the Company consisted primarily of GNMA, FNMA and FHLMC pass-through certificates which are guaranteed by those respective agencies of the United States government (Government Sponsored Enterprise, GSEs).

The following table shows the contractual maturities of investments in debt securities available-for-sale at June 30, 2017. Expected maturities will differ from contractual maturities, because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.



(Dollars in thousands)	Amortized Cost		Fair Value
Due in one year or less	$	113,082	$	113,466
Due after one year through five years	423,816		422,703
Due after five years through ten years	53,019		52,840
Due after ten years	—		—
Mortgage-backed securities	255,747		255,698
Total debt securities available-for-sale	$	845,664	$	844,707

The following table summarizes gross unrealized losses and fair value by investment category and age.



	Less than 12 Months					12 months or Longer					Total
(Dollars in thousands)	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
June 30, 2017
U.S. Treasury and Federal agencies securities	$	267,261	$	(2,229	)	$	22,015	$	(381	)	$	289,276	$	(2,610	)
U.S. States and political subdivisions securities	35,592		(323		)	7,493		(166		)	43,085		(489		)
Mortgage-backed securities - Federal agencies	125,053		(1,656		)	30,536		(503		)	155,589		(2,159		)
Corporate debt securities	11,910		(159		)	—		—			11,910		(159		)
Foreign government and other securities	—		—			—		—			—		—
Total debt securities	439,816		(4,367		)	60,044		(1,050		)	499,860		(5,417		)
Marketable equity securities	—		—			3		(1		)	3		(1		)
Total investment securities available-for-sale	$	439,816	$	(4,367	)	$	60,047	$	(1,051	)	$	499,863	$	(5,418	)

December 31, 2016
U.S. Treasury and Federal agencies securities	$	263,680	$	(4,471	)	$	—	$	—		$	263,680	$	(4,471	)
U.S. States and political subdivisions securities	74,129		(1,515		)	3,337		(55		)	77,466		(1,570		)
Mortgage-backed securities - Federal agencies	168,554		(2,341		)	5,102		(241		)	173,656		(2,582		)
Corporate debt securities	13,312		(301		)	—		—			13,312		(301		)
Foreign government and other securities	—		—			—		—			—		—
Total debt securities	519,675		(8,628		)	8,439		(296		)	528,114		(8,924		)
Marketable equity securities	280		(70		)	4		—			284		(70		)
Total investment securities available-for-sale	$	519,955	$	(8,698	)	$	8,443	$	(296	)	$	528,398	$	(8,994	)

The initial indication of potential other-than-temporary-impairment (OTTI) for both debt and equity securities is a decline in fair value below amortized cost. Quarterly, the impaired securities are analyzed on a qualitative and quantitative basis in determining OTTI. Declines in the fair value of available-for-sale debt securities below their cost that are deemed to be other-than-temporary are reflected in earnings as realized losses to the extent the impairment is related to credit losses. The amount of impairment related to other factors is recognized in other comprehensive income. In estimating OTTI losses, the Company considers among other things, (i) the length of time and the extent to which fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer, and (iii) whether it is more likely than not that the Company will not have to sell any such securities before a recovery of cost.

At June 30, 2017, the Company does not have the intent to sell any of the available-for-sale securities in the table above and believes that it is more likely than not, that it will not have to sell any such securities before an anticipated recovery of cost. Primarily the unrealized losses on debt securities are due to increases in market rates over the yields available at the time the underlying securities were purchased. The fair value is expected to recover on all debt securities as they approach their maturity date or re-pricing date or if market yields for such investments decline. The Company does not believe any of the securities are impaired due to reasons of credit quality.

The following table shows the gross realized gains and losses from the securities available-for-sale portfolio, including marketable equity securities. Realized gains and losses of all securities are computed using the specific identification cost basis.



	Three Months Ended June 30,						Six Months Ended June 30,
(Dollars in thousands)	2017			2016			2017			2016
Gross realized gains	$	655		$	85		$	1,940		$	95
Gross realized losses	—			—			—			—
OTTI losses	(190		)	(294		)	(190		)	(294		)
Net realized gains (losses)	$	465		$	(209	)	$	1,750		$	(199	)

At June 30, 2017 and December 31, 2016, investment securities available-for-sale with carrying values of $277.31 million and $276.29 million, respectively, were pledged as collateral for security repurchase agreements and for other purposes.