Securities Available for Sale and Held to Maturity (Tables)

6 Months Ended

Jun. 30, 2020

Investments Debt And Equity Securities [Abstract]

Securities Held to Maturity by Credit Rating, as Determined by Moody's

The following table presents the amortized cost of Trustmark’s securities held to maturity by credit rating, as determined by Moody’s, at June 30, 2020 ($ in thousands):

	Securities Held to Maturity
June 30, 2020	Amortized Cost
Aaa	$	628,419
Aa1 to Aa3		26,179
Not Rated (1)		5,450
Total	$	660,048

(1) Not rated securities primarily consist of Mississippi municipal general obligations.

Amortized Cost and Estimated Fair Value of Available for Sale and Held to Maturity Securities

The following tables are a summary of the amortized cost and estimated fair value of securities available for sale and held to maturity at June 30, 2020 and December 31, 2019 ($ in thousands):

	Securities Available for Sale									Securities Held to Maturity
June 30, 2020	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. Government agency obligations	$	20,254	$	160	$	(516	)	$	19,898	$	—	$	—	$	—		$	—
Obligations of states and political    subdivisions		10,565		611		—			11,176		31,629		461		(25	)		32,065
Mortgage-backed securities
Residential mortgage pass-through    securities
Guaranteed by GNMA		67,439		2,199		(1	)		69,637		10,306		548		—			10,854
Issued by FNMA and FHLMC		1,096,861		24,762		(19	)		1,121,604		86,346		3,204		—			89,550
Other residential mortgage-backed    securities
Issued or guaranteed by FNMA,    FHLMC or GNMA		560,109		14,846		(15	)		574,940		435,333		23,148		—			458,481
Commercial mortgage-backed securities
Issued or guaranteed by FNMA,    FHLMC or GNMA		84,350		2,558		(10	)		86,898		96,434		3,177		—			99,611
Total	$	1,839,578	$	45,136	$	(561	)	$	1,884,153	$	660,048	$	30,538	$	(25	)	$	690,561
December 31, 2019
U.S. Government agency obligations	$	22,965	$	69	$	(707	)	$	22,327	$	3,781	$	220	$	—		$	4,001
Obligations of states and political    subdivisions		24,952		513		—			25,465		31,781		434		(53	)		32,162
Mortgage-backed securities
Residential mortgage pass-through    securities
Guaranteed by GNMA		69,196		425		(369	)		69,252		10,820		266		(10	)		11,076
Issued by FNMA and FHLMC		714,350		2,171		(3,165	)		713,356		96,631		286		(370	)		96,547
Other residential mortgage-backed    securities
Issued or guaranteed by FNMA,    FHLMC or GNMA		656,162		3,777		(1,713	)		658,226		485,324		7,026		(656	)		491,694
Commercial mortgage-backed securities
Issued or guaranteed by FNMA,    FHLMC or GNMA		113,359		625		(206	)		113,778		109,762		1,042		(82	)		110,722
Total	$	1,600,984	$	7,580	$	(6,160	)	$	1,602,404	$	738,099	$	9,274	$	(1,171	)	$	746,202

Securities with Gross Unrealized Losses, Segregated by Length of Impairment

The tables below include securities with gross unrealized losses for which an allowance for credit losses has not been recorded and segregated by length of impairment at June 30, 2020 and December 31, 2019 ($ in thousands):

	Less than 12 Months					12 Months or More					Total
June 30, 2020	Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses
U.S. Government agency obligations	$	—	$	—		$	11,624	$	(516	)	$	11,624	$	(516	)
Obligations of states and political subdivisions		—		—			6,221		(25	)		6,221		(25	)
Mortgage-backed securities
Residential mortgage pass-through securities
Guaranteed by GNMA		325		(1	)		—		—			325		(1	)
Issued by FNMA and FHLMC		20,644		(7	)		8,954		(12	)		29,598		(19	)
Other residential mortgage-backed securities
Issued or guaranteed by FNMA, FHLMC or    GNMA		2,436		(15	)		—		—			2,436		(15	)
Commercial mortgage-backed securities
Issued or guaranteed by FNMA, FHLMC or    GNMA		—		—			668		(10	)		668		(10	)
Total	$	23,405	$	(23	)	$	27,467	$	(563	)	$	50,872	$	(586	)
December 31, 2019
U.S. Government agency obligations	$	6,585	$	(105	)	$	12,886	$	(602	)	$	19,471	$	(707	)
Obligations of states and political subdivisions		—		—			6,216		(53	)		6,216		(53	)
Mortgage-backed securities
Residential mortgage pass-through securities
Guaranteed by GNMA		23,544		(107	)		18,529		(272	)		42,073		(379	)
Issued by FNMA and FHLMC		112,879		(230	)		278,120		(3,305	)		390,999		(3,535	)
Other residential mortgage-backed securities
Issued or guaranteed by FNMA, FHLMC or    GNMA		158,341		(738	)		151,271		(1,631	)		309,612		(2,369	)
Commercial mortgage-backed securities
Issued or guaranteed by FNMA, FHLMC or    GNMA		51,312		(167	)		14,155		(121	)		65,467		(288	)
Total	$	352,661	$	(1,347	)	$	481,177	$	(5,984	)	$	833,838	$	(7,331	)

Contractual Maturities of Available for Sale and Held to Maturity Securities

The amortized cost and estimated fair value of securities available for sale and held to maturity at June 30, 2020, by contractual maturity, are shown below ($ in thousands).  Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.

	Securities Available for Sale				Securities Held to Maturity
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in one year or less	$	7,867	$	7,945	$	18,599	$	18,715
Due after one year through five years		1,559		1,601		13,030		13,350
Due after five years through ten years		2,161		2,112		—		—
Due after ten years		19,232		19,416		—		—
		30,819		31,074		31,629		32,065
Mortgage-backed securities		1,808,759		1,853,079		628,419		658,496
Total	$	1,839,578	$	1,884,153	$	660,048	$	690,561