Securities (Tables)

9 Months Ended

Sep. 30, 2019

Securities

Schedule of amortized cost, unrealized gains and losses and fair values of securities classified available for sale and held to maturity

The table below provides the amortized cost, unrealized gains and losses and fair values of debt securities summarized by major category (dollars in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
September 30, 2019:	Cost		Gains		Losses		Value
Debt securities available for sale
U.S. Treasury securities	$	51,395	$	262	$	(6)	$	51,651
Obligations of U.S. government corporations and agencies		202,393		3,273		(53)		205,613
Obligations of states and political subdivisions		263,345		5,733		(16)		269,062
Commercial mortgage-backed securities		121,338		2,248		(18)		123,568
Residential mortgage-backed securities		914,320		12,674		(607)		926,387
Corporate debt securities		123,061		1,668		(5)		124,724
Total	$	1,675,852	$	25,858	$	(705)	$	1,701,005
Debt securities held to maturity
Obligations of states and political subdivisions	$	15,170	$	229	$	—	$	15,399

			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
December 31, 2018:	Cost		Gains		Losses		Value
Debt securities available for sale
U.S. Treasury securities	$	25,824	$	1	$	(414)	$	25,411
Obligations of U.S. government corporations and agencies		53,096		7		(761)		52,342
Obligations of states and political subdivisions		171,131		484		(1,571)		170,044
Commercial mortgage-backed securities		2,003		—		(61)		1,942
Residential mortgage-backed securities		322,646		245		(7,143)		315,748
Corporate debt securities		132,513		61		(376)		132,198
Total	$	707,213	$	798	$	(10,326)	$	697,685
Debt securities held to maturity
Obligations of states and political subdivisions	$	33,947	$	68	$	(87)	$	33,928
Commercial mortgage-backed securities		59,054		11		(1,003)		58,062
Residential mortgage-backed securities		515,659		1,748		(6,037)		511,370
Total	$	608,660	$	1,827	$	(7,127)	$	603,360

Schedule of amortized cost and fair value of debt securities available for sale and held to maturity by contractual maturity

The amortized cost and fair value of debt securities, by contractual maturity or pre-refunded date, are shown below. Mortgages underlying mortgage-backed securities may be called or prepaid; therefore, actual maturities could differ from the contractual maturities. All mortgage-backed securities were issued by U.S. government agencies and corporations (dollars in thousands).

	Debt securities available for sale				Debt securities held to maturity
	Amortized		Fair		Amortized		Fair
September 30, 2019:	Cost		Value		Cost		Value
Due in one year or less	$	128,897	$	129,230	$	2,215	$	2,218
Due after one year through five years		407,251		413,491		11,834		12,006
Due after five years through ten years		248,270		253,453		1,121		1,175
Due after ten years		891,434		904,831		—		—
Total	$	1,675,852	$	1,701,005	$	15,170	$	15,399

Schedule of realized gains and losses related to sales of securities

Realized gains and losses related to sales and calls of debt securities available for sale are summarized as follows (dollars in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2018		2019		2018
Gross security gains	$	298	$	—	$	689	$	—
Gross security (losses)		(1)		—		(585)		—
Net (losses) gains on sales of securities(1)	$	297	$	—	$	104	$	—

(1) Net (losses) gains on sales of securities reported on the unaudited Consolidated Statements of Income includes sale of equity securities, excluded in this table.

Schedule of securities with gross unrealized losses aggregated by investment category and length of time that individual securities have been in a continuous loss position

The following information pertains to debt securities with gross unrealized losses, aggregated by investment category and the length of time that individual securities have been in a continuous loss position (dollars in thousands):

	For less than				For greater
	12 months, gross				than 12 months, gross				Total, gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
September 30, 2019:	Value		Losses		Value		Losses		Value		Losses
Debt securities available for sale
U.S. Treasury securities	$	—	$	—	$	9,982	$	(6)	$	9,982	$	(6)
Obligations of U.S. government corporations and agencies		6,938		(45)		6,481		(8)		13,419		(53)
Obligations of states and political subdivisions		4,949		(11)		9,129		(5)		14,078		(16)
Commercial mortgage-backed securities		3,913		(11)		9,702		(7)		13,615		(18)
Residential mortgage-backed securities		43,372		(47)		57,319		(560)		100,691		(607)
Corporate debt securities		485		(2)		5,595		(3)		6,080		(5)
Total temporarily impaired securities	$	59,657	$	(116)	$	98,208	$	(589)	$	157,865	$	(705)

	For less than				For greater
	12 months, gross				than 12 months, gross				Total, gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
December 31, 2018:	Value		Losses		Value		Losses		Value		Losses
Debt securities available for sale
U.S. Treasury securities	$	995	$	(4)	$	24,343	$	(410)	$	25,338	$	(414)
Obligations of U.S. government corporations and agencies		749		(3)		50,744		(758)		51,493		(761)
Obligations of states and political subdivisions		49,893		(460)		77,651		(1,111)		127,544		(1,571)
Commercial mortgage-backed securities		—		—		1,942		(61)		1,942		(61)
Residential mortgage-backed securities		48,387		(496)		247,573		(6,647)		295,960		(7,143)
Corporate debt securities		90,713		(268)		15,083		(108)		105,796		(376)
Total temporarily impaired securities	$	190,737	$	(1,231)	$	417,336	$	(9,095)	$	608,073	$	(10,326)
Debt securities held to maturity
Obligations of states and political subdivisions	$	9,531	$	(33)	$	9,538	$	(54)	$	19,069	$	(87)
Commercial mortgage-backed securities		12,067		(212)		45,041		(791)		57,108		(1,003)
Residential mortgage-backed securities		77,071		(974)		245,128		(5,063)		322,199		(6,037)
Total temporarily impaired securities	$	98,669	$	(1,219)	$	299,707	$	(5,908)	$	398,376	$	(7,127)