Investment Securities (Tables)

6 Months Ended

Jun. 30, 2022

Investments, Debt and Equity Securities [Abstract]

Investment securities available for sale

The amortized cost and fair values of AFS and HTM securities at June 30, 2022 were as follows:

($ in Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
AFS investment securities
U. S. Treasury securities	$	124,365	$	—	$	(11,256)	$	113,109
Agency securities	15,000		—		(1,041)		13,959
Obligations of state and political subdivisions (municipal securities)	361,712		648		(3,518)		358,842
Residential mortgage-related securities
FNMA / FHLMC	1,959,641		547		(148,585)		1,811,603
GNMA	87,779		—		(1,542)		86,238
Commercial mortgage-related securities
FNMA / FHLMC	19,207		—		(601)		18,606
GNMA	108,153		—		(2,473)		105,680
Asset backed securities
FFELP	168,357		—		(7,092)		161,264
SBA	5,287		40		(45)		5,281
Other debt securities	3,000		—		(71)		2,929
Total AFS investment securities	$	2,852,501	$	1,234	$	(176,224)	$	2,677,511
HTM investment securities
U. S. Treasury securities	$	998	$	—	$	(44)	$	955
Obligations of state and political subdivisions (municipal securities)	1,717,627		4,002		(161,116)		1,560,514
Residential mortgage-related securities
FNMA / FHLMC	967,421		34,108		(125,444)		876,085
GNMA	42,248		37		(1,637)		40,649
Private-label	375,638		12,693		(54,490)		333,841
Commercial mortgage-related securities
FNMA/FHLMC	762,086		16,835		(131,851)		647,070
GNMA	79,250		799		(4,970)		75,079
Total HTM investment securities	$	3,945,269	$	68,474	$	(479,551)	$	3,534,192

During the first quarter of 2022, the Corporation redesignated approximately $1.6 billion of mortgage-related securities from AFS to HTM. The reclassification of these investment securities was accounted for at fair value. Management elected to transfer these investment securities as the Corporation has the positive intent and ability to hold these investment securities to maturity. See Note 16 for additional information on the unrealized losses on investment securities transferred from AFS to HTM. The amortized cost and fair values of AFS and HTM securities at December 31, 2021 were as follows:

($ in Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
AFS investment securities
U. S. Treasury securities	$	124,291	$	—	$	(1,334)	$	122,957
Agency securities	15,000		—		(103)		14,897
Obligations of state and political subdivisions (municipal securities)	381,517		18,940		—		400,457
Residential mortgage-related securities
FNMA / FHLMC	2,709,399		3,729		(21,249)		2,691,879
GNMA	66,189		1,591		—		67,780
Private-label	332,028		31		(2,335)		329,724
Commercial mortgage-related securities
FNMA / FHLMC	357,240		2,686		(9,302)		350,623
GNMA	165,439		1,360		—		166,799
Asset backed securities
FFELP	177,974		475		(1,123)		177,325
SBA	6,594		39		(54)		6,580
Other debt securities	3,000		—		(6)		2,994
Total AFS investment securities	$	4,338,671	$	28,850	$	(35,506)	$	4,332,015
HTM investment securities
U. S. Treasury securities	$	1,000	$	1	$	—	$	1,001
Obligations of state and political subdivisions (municipal securities)	1,628,759		113,179		(1,951)		1,739,988
Residential mortgage-related securities
FNMA / FHLMC	34,347		1,792		—		36,139
GNMA	48,053		1,578		—		49,631
Commercial mortgage-related securities
FNMA / FHLMC	425,937		122		(6,659)		419,400
GNMA	100,907		1,799		(200)		102,506
Total HTM investment securities	$	2,239,003	$	118,471	$	(8,809)	$	2,348,664

Investment securities held to maturity

The amortized cost and fair values of AFS and HTM securities at June 30, 2022 were as follows:

($ in Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
AFS investment securities
U. S. Treasury securities	$	124,365	$	—	$	(11,256)	$	113,109
Agency securities	15,000		—		(1,041)		13,959
Obligations of state and political subdivisions (municipal securities)	361,712		648		(3,518)		358,842
Residential mortgage-related securities
FNMA / FHLMC	1,959,641		547		(148,585)		1,811,603
GNMA	87,779		—		(1,542)		86,238
Commercial mortgage-related securities
FNMA / FHLMC	19,207		—		(601)		18,606
GNMA	108,153		—		(2,473)		105,680
Asset backed securities
FFELP	168,357		—		(7,092)		161,264
SBA	5,287		40		(45)		5,281
Other debt securities	3,000		—		(71)		2,929
Total AFS investment securities	$	2,852,501	$	1,234	$	(176,224)	$	2,677,511
HTM investment securities
U. S. Treasury securities	$	998	$	—	$	(44)	$	955
Obligations of state and political subdivisions (municipal securities)	1,717,627		4,002		(161,116)		1,560,514
Residential mortgage-related securities
FNMA / FHLMC	967,421		34,108		(125,444)		876,085
GNMA	42,248		37		(1,637)		40,649
Private-label	375,638		12,693		(54,490)		333,841
Commercial mortgage-related securities
FNMA/FHLMC	762,086		16,835		(131,851)		647,070
GNMA	79,250		799		(4,970)		75,079
Total HTM investment securities	$	3,945,269	$	68,474	$	(479,551)	$	3,534,192

During the first quarter of 2022, the Corporation redesignated approximately $1.6 billion of mortgage-related securities from AFS to HTM. The reclassification of these investment securities was accounted for at fair value. Management elected to transfer these investment securities as the Corporation has the positive intent and ability to hold these investment securities to maturity. See Note 16 for additional information on the unrealized losses on investment securities transferred from AFS to HTM. The amortized cost and fair values of AFS and HTM securities at December 31, 2021 were as follows:

($ in Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
AFS investment securities
U. S. Treasury securities	$	124,291	$	—	$	(1,334)	$	122,957
Agency securities	15,000		—		(103)		14,897
Obligations of state and political subdivisions (municipal securities)	381,517		18,940		—		400,457
Residential mortgage-related securities
FNMA / FHLMC	2,709,399		3,729		(21,249)		2,691,879
GNMA	66,189		1,591		—		67,780
Private-label	332,028		31		(2,335)		329,724
Commercial mortgage-related securities
FNMA / FHLMC	357,240		2,686		(9,302)		350,623
GNMA	165,439		1,360		—		166,799
Asset backed securities
FFELP	177,974		475		(1,123)		177,325
SBA	6,594		39		(54)		6,580
Other debt securities	3,000		—		(6)		2,994
Total AFS investment securities	$	4,338,671	$	28,850	$	(35,506)	$	4,332,015
HTM investment securities
U. S. Treasury securities	$	1,000	$	1	$	—	$	1,001
Obligations of state and political subdivisions (municipal securities)	1,628,759		113,179		(1,951)		1,739,988
Residential mortgage-related securities
FNMA / FHLMC	34,347		1,792		—		36,139
GNMA	48,053		1,578		—		49,631
Commercial mortgage-related securities
FNMA / FHLMC	425,937		122		(6,659)		419,400
GNMA	100,907		1,799		(200)		102,506
Total HTM investment securities	$	2,239,003	$	118,471	$	(8,809)	$	2,348,664

Amortized cost and fair values of investment securities by contractual maturity

The expected maturities of AFS and HTM securities at June 30, 2022, are shown below:

	AFS					HTM
($ in Thousands)	Amortized Cost		Fair Value			Amortized Cost		Fair Value
Due in one year or less	$	6,905	$	6,895		$	15,582	$	15,627
Due after one year through five years	98,473		94,572			34,915		35,027
Due after five years through ten years	361,344		350,609			169,413		167,713
Due after ten years	37,355		36,762			1,498,715		1,343,101
Total debt securities	504,077		488,839			1,718,625		1,561,468
Residential mortgage-related securities
FNMA / FHLMC	1,959,641		1,811,603			967,421		876,085
GNMA	87,779		86,238			42,248		40,649
Private-label	—		—			375,638		333,841
Commercial mortgage-related securities
FNMA / FHLMC	19,207		18,606			762,086		647,070
GNMA	108,153		105,680			79,250		75,079
Asset backed securities
FFELP	168,357		161,264			—		—
SBA	5,287		5,281			—		—
Total investment securities	$	2,852,501	$	2,677,511		$	3,945,269	$	3,534,192
Ratio of fair value to amortized cost			93.9		%			89.6		%

Debt Securities, Held-to-maturity, Credit Quality Indicator

The following table summarizes the credit quality indicators of HTM securities at amortized cost at June 30, 2022:

($ in Thousands)	AAA		AA		A		Not Rated		Total
U. S. Treasury securities	$	998	$	—	$	—	$	—	$	998
Obligations of state and political subdivisions (municipal securities)	799,925		908,098		8,710		894		1,717,627
Residential mortgage-related securities
FNMA / FHLMC	967,421		—		—		—		967,421
GNMA	42,248		—		—		—		42,248
Private-label	375,638		—		—		—		375,638
Commercial mortgage-related securities
FNMA / FHLMC	762,086		—		—		—		762,086
GNMA	79,250		—		—		—		79,250
Total HTM securities	$	3,027,567	$	908,098	$	8,710	$	894	$	3,945,269

The following table summarizes the credit quality indicators of HTM securities at amortized cost at December 31, 2021:

($ in Thousands)	AAA		AA		A		Not Rated		Total
U. S. Treasury securities	$	1,000	$	—	$	—	$	—	$	1,000
Obligations of state and political subdivisions (municipal securities)	702,399		914,591		10,873		896		1,628,759
Residential mortgage-related securities
FNMA / FHLMC	34,347		—		—		—		34,347
GNMA	48,053		—		—		—		48,053
Commercial mortgage-related securities
FNMA / FHLMC	425,937		—		—		—		425,937
GNMA	100,907		—		—		—		100,907
Total HTM securities	$	1,312,642	$	914,591	$	10,873	$	896	$	2,239,003

Realized gains and losses and proceeds from sale

The proceeds from the sale of AFS investment securities for the three and six months ended June 30, 2022 and 2021, are shown below:

	Three Months Ended Jun 30,				Six Months Ended Jun 30,
($ in Thousands)	2022		2021		2022		2021
Gross gains on AFS securities	$	—	$	386	$	21	$	421
Gross (losses) on AFS securities	(8)		(362)		(8)		(437)
Investment securities gains (losses), net	$	(8)	$	24	$	12	$	(16)
Proceeds from sales of AFS investment securities	$	327	$	107,412	$	1,061	$	158,708

Unrealized losses and fair value of available for sale and held to maturity securities, by investment category and time length

The following represents gross unrealized losses and the related fair value of AFS and HTM securities, aggregated by investment category and length of time individual securities have been in a continuous unrealized loss position, at June 30, 2022:

	Less than 12 months					12 months or more					Total
($ in Thousands)	Number of Securities	Unrealized (Losses)		Fair Value		Number of Securities	Unrealized (Losses)		Fair Value		Unrealized (Losses)		Fair Value
AFS investment securities
U.S. Treasury securities	5	$	(10,141)	$	104,289	2	$	(1,115)	$	8,820	$	(11,256)	$	113,109
Agency securities	1	(1,041)		13,959		—	—		—		(1,041)		13,959
Obligations of state and political subdivisions (municipal securities)	373	(3,518)		224,804		—	—		—		(3,518)		224,804
Residential mortgage-related securities
FNMA / FHLMC	95	(125,142)		1,554,774		8	(23,443)		222,626		(148,585)		1,777,400
GNMA	17	(1,542)		86,238		—	—		—		(1,542)		86,238
Commercial mortgage-related securities
FNMA / FHLMC	1	(601)		18,606		—	—		—		(601)		18,606
GNMA	35	(2,473)		105,680		—	—		—		(2,473)		105,680
Asset backed securities
FFELP	6	(2,905)		72,610		9	(4,187)		88,655		(7,092)		161,264
SBA	—	—		—		7	(45)		2,456		(45)		2,456
Other debt securities	3	(71)		2,929		—	—		—		(71)		2,929
Total	536	$	(147,433)	$	2,183,889	26	$	(28,791)	$	322,556	$	(176,224)	$	2,506,446
HTM investment securities
U.S. Treasury securities	1	$	(44)	$	955	—	$	—	$	—	$	(44)	$	955
Obligations of state and political subdivisions (municipal securities)	717	(156,757)		1,127,009		9	(4,359)		11,242		(161,116)		1,138,251
Residential mortgage-related securities
FNMA / FHLMC	81	(125,444)		872,561		—	—		—		(125,444)		872,561
GNMA	74	(1,637)		40,113		—	—		—		(1,637)		40,113
Private-label	18	(54,490)		333,841		—	—		—		(54,490)		333,841
Commercial mortgage-related securities
FNMA / FHLMC	15	(119,046)		313,359		7	(12,804)		68,980		(131,851)		382,339
GNMA	33	(4,970)		339,810		—	—		—		(4,970)		339,810
Total	939	$	(462,387)	$	3,027,647	16	$	(17,163)	$	80,222	$	(479,551)	$	3,107,869

For comparative purposes, the following represents gross unrealized losses and the related fair value of AFS and HTM securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at December 31, 2021:

	Less than 12 months					12 months or more					Total
($ in Thousands)	Number of Securities	Unrealized (Losses)		Fair Value		Number of Securities	Unrealized (Losses)		Fair Value		Unrealized (Losses)		Fair Value
AFS investment securities
U.S. Treasury securities	7	$	(1,334)	$	122,957	—	$	—	$	—	$	(1,334)	$	122,957
Agency securities	1	(103)		14,897		—	—		—		(103)		14,897
Residential mortgage-related securities
FNMA / FHLMC	74	(21,249)		2,172,837		—	—		—		(21,249)		2,172,837
Private-label	12	(2,335)		248,617		—	—		—		(2,335)		248,617
FNMA / FHLMC commercial mortgage-related securities	19	(9,302)		328,568		—	—		—		(9,302)		328,568
Asset backed securities
FFELP	4	(256)		64,282		8	(867)		62,576		(1,123)		126,858
SBA	—	—		—		9	(54)		3,902		(54)		3,902
Other debt securities	3	(6)		2,994		—	—		—		(6)		2,994
Total	120	$	(34,586)	$	2,955,152	17	$	(920)	$	66,478	$	(35,506)	$	3,021,630
HTM investment securities
Obligations of state and political subdivisions (municipal securities)	49	$	(1,951)	$	112,038	—	$	—	$	—	$	(1,951)	$	112,038
Commercial mortgage-related securities
FNMA/FHLMC	18	(6,272)		388,072		1	(387)		10,775		(6,659)		398,847
GNMA	5	(200)		33,468		—	—		—		(200)		33,468
Total	72	$	(8,422)	$	533,577	1	$	(387)	$	10,775	$	(8,809)	$	544,352