Securities (Tables)

12 Months Ended

Dec. 31, 2024

Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]

Amortized Cost and Fair Value of Debt Securities Available for Sale

Securities Available for Sale
	December 31, 2024								December 31, 2023
			Gross		Gross						Gross		Gross
	Amortized		Unrealized		Unrealized		Fair		Amortized		Unrealized		Unrealized		Fair
($ in thousands)	Cost		Gains		Losses		Value		Cost		Gains		Losses		Value
U.S. Treasury and government agency    securities	$	185,827	$	349	$	3,894	$	182,282	$	97,741	$	1,581	$	1,514	$	97,808
Municipal obligations		200,272		—		3,942		196,330		203,533		79		2,200		201,412
Residential mortgage-backed securities		2,482,109		496		353,554		2,129,051		2,440,411		2,734		329,279		2,113,866
Commercial mortgage-backed securities		2,849,372		2,185		250,592		2,600,965		2,683,872		7,176		253,576		2,437,472
Collateralized mortgage obligations		37,553		—		2,306		35,247		47,661		—		3,376		44,285
Corporate debt securities		19,000		—		1,384		17,616		23,500		—		3,148		20,352
Total	$	5,774,133	$	3,030	$	615,672	$	5,161,491	$	5,496,718	$	11,570	$	593,093	$	4,915,195

Amortized Cost and Fair Value of Debt Securities Held to Maturity

Securities Held to Maturity
	December 31, 2024								December 31, 2023
			Gross		Gross						Gross		Gross
	Amortized		Unrealized		Unrealized		Fair		Amortized		Unrealized		Unrealized		Fair
($ in thousands)	Cost		Gains		Losses		Value		Cost		Gains		Losses		Value
U.S. Treasury and government agency    securities	$	394,689	$	—	$	45,876	$	348,813	$	413,490	$	179	$	43,971	$	369,698
Municipal obligations		623,907		169		20,867		603,209		664,488		1,252		19,593		646,147
Residential mortgage-backed securities		573,057		—		61,525		511,532		654,262		—		59,223		595,039
Commercial mortgage-backed securities		818,604		—		72,854		745,750		920,048		—		75,803		844,245
Collateralized mortgage obligations		25,406		—		1,184		24,222		32,491		—		1,702		30,789
Total	$	2,435,663	$	169	$	202,306	$	2,233,526	$	2,684,779	$	1,431	$	200,292	$	2,485,918

Proceeds from Gross Gains on and Gross Losses on Sale of Securities

The following table presents the proceeds from, gross gains on, and gross losses on sales of securities during the years ended December 31, 2024, 2023 and 2022. Net gains or losses are reflected in the "Securities transactions, net" line item on the Consolidated Statements of Income.

	Years Ended December 31,
($ in thousands)	2024		2023		2022
Proceeds	$	—	$	977,114	$	73,219
Gross gains		—		—		—
Gross losses		—		65,380		87

Available for Sale Securities [Member]

Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]

Amortized Cost and Fair Value of Debt Securities by Contractual Maturity

($ in thousands)	Amortized Cost		Fair Value
Debt Securities Available for Sale
Due in one year or less	$	36,791	$	36,914
Due after one year through five years		958,196		924,308
Due after five years through ten years		2,330,532		2,099,062
Due after ten years		2,448,614		2,101,207
Total available for sale debt securities	$	5,774,133	$	5,161,491

Securities with Unrealized Losses

Available for sale
	December 31, 2024
	Losses < 12 Months				Losses 12 Months or >				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
($ in thousands)	Value		Losses		Value		Losses		Value		Losses
U.S. Treasury and government agency securities	$	130,453	$	2,243	$	7,247	$	1,651	$	137,700	$	3,894
Municipal obligations		24,149		247		170,110		3,695		194,259		3,942
Residential mortgage-backed securities		347,772		2,935		1,554,001		350,619		1,901,773		353,554
Commercial mortgage-backed securities		184,534		2,738		2,139,191		247,854		2,323,725		250,592
Collateralized mortgage obligations		—		—		35,247		2,306		35,247		2,306
Corporate debt securities		—		—		15,616		1,384		15,616		1,384
Total	$	686,908	$	8,163	$	3,921,412	$	607,509	$	4,608,320	$	615,672

Available for sale
	December 31, 2023
	Losses < 12 Months				Losses 12 Months or >				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
($ in thousands)	Value		Losses		Value		Losses		Value		Losses
U.S. Treasury and government agency securities	$	—	$	—	$	7,790	$	1,514	$	7,790	$	1,514
Municipal obligations		49,832		374		128,965		1,826		178,797		2,200
Residential mortgage-backed securities		3,062		25		1,795,154		329,254		1,798,216		329,279
Commercial mortgage-backed securities		—		—		2,227,703		253,576		2,227,703		253,576
Collateralized mortgage obligations		—		—		44,285		3,376		44,285		3,376
Corporate debt securities		—		—		19,852		3,148		19,852		3,148
Total	$	52,894	$	399	$	4,223,749	$	592,694	$	4,276,643	$	593,093

Held-to-maturity Securities [Member]

Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]

Amortized Cost and Fair Value of Debt Securities by Contractual Maturity

($ in thousands)	Amortized Cost		Fair Value
Debt Securities Held to Maturity
Due in one year or less	$	105,692	$	105,035
Due after one year through five years		780,633		740,241
Due after five years through ten years		572,371		535,864
Due after ten years		976,967		852,386
Total held to maturity debt securities	$	2,435,663	$	2,233,526

Securities with Unrealized Losses

Held to maturity
	December 31, 2024
	Losses < 12 Months				Losses 12 Months or >				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
($ in thousands)	Value		Losses		Value		Losses		Value		Losses
U.S. Treasury and government agency securities	$	27,660	$	840	$	321,154	$	45,036	$	348,814	$	45,876
Municipal obligations		82,028		451		497,999		20,416		580,027		20,867
Residential mortgage-backed securities		—		—		511,531		61,525		511,531		61,525
Commercial mortgage-backed securities		—		—		745,750		72,854		745,750		72,854
Collateralized mortgage obligations		—		—		24,222		1,184		24,222		1,184
Total	$	109,688	$	1,291	$	2,100,656	$	201,015	$	2,210,344	$	202,306

Held to maturity	December 31, 2023
	Losses < 12 Months				Losses 12 Months or >				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
($ in thousands)	Value		Losses		Value		Losses		Value		Losses
U.S. Treasury and government agency securities	$	9,530	$	63	$	339,533	$	43,908	$	349,063	$	43,971
Municipal obligations		343,401		1,801		226,165		17,792		569,566		19,593
Residential mortgage-backed securities		—		—		595,039		59,223		595,039		59,223
Commercial mortgage-backed securities		—		—		844,245		75,803		844,245		75,803
Collateralized mortgage obligations		—		—		30,789		1,702		30,789		1,702
Total	$	352,931	$	1,864	$	2,035,771	$	198,428	$	2,388,702	$	200,292