Securities (Tables)

9 Months Ended

Sep. 30, 2023

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

	September 30, 2023								December 31, 2022
			Gross		Gross						Gross		Gross
Securities Available for Sale	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	$	118,208	$	—	$	4,018	$	114,190	$	113,211	$	—	$	2,346	$	110,865
Municipal obligations		204,445		44		11,378		193,111		207,014		59		3,981		203,092
Residential mortgage-backed securities		2,424,225		24		463,682		1,960,567		2,655,381		224		398,619		2,256,986
Commercial mortgage-backed securities		3,250,230		—		408,879		2,841,351		3,234,278		2,032		342,880		2,893,430
Collateralized mortgage obligations		64,701		—		5,871		58,830		76,830		—		6,242		70,588
Corporate debt securities		23,500		—		3,393		20,107		23,500		—		2,420		21,080
Total	$	6,085,309	$	68	$	897,221	$	5,188,156	$	6,310,214	$	2,315	$	756,488	$	5,556,041

Amortized Cost and Fair Value of Debt Securities Held to Maturity

	September 30, 2023								December 31, 2022
			Gross		Gross						Gross		Gross
Securities Held to Maturity	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	$	418,323	$	—	$	60,006	$	358,317	$	426,454	$	21	$	49,044	$	377,431
Municipal obligations		667,809		—		39,068		628,741		698,908		753		26,558		673,103
Residential mortgage-backed securities		673,898		—		88,902		584,996		734,478		—		72,532		661,946
Commercial mortgage-backed securities		933,260		—		107,231		826,029		948,691		—		87,211		861,480
Collateralized mortgage obligations		34,655		—		2,451		32,204		43,964		—		2,526		41,438
Total	$	2,727,945	$	—	$	297,658	$	2,430,287	$	2,852,495	$	774	$	237,871	$	2,615,398

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 nine months ended September 30, 2023 and 2022. Net gains or losses are reflected in the "Securities transactions, net" line item on the Consolidated Statements of Income.

	Nine Months Ended  September 30,
($ in thousands)	2023		2022
Proceeds	$	—	$	73,219
Gross gains		—		—
Gross losses		—		87
Net loss	$	—	$	(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

Debt Securities Available for Sale	Amortized		Fair
($ in thousands)	cost		value
Due in one year or less	$	17,746	$	17,540
Due after one year through five years		1,018,866		957,682
Due after five years through ten years		2,995,003		2,592,296
Due after ten years		2,053,694		1,620,638
Total available for sale debt securities	$	6,085,309	$	5,188,156

Securities with Unrealized Losses

Available for Sale
September 30, 2023	Losses < 12 months				Losses 12 months or >				Total
($ in thousands)	Fair value		Gross unrealized losses		Fair value		Gross unrealized losses		Fair value		Gross unrealized losses
U.S. Treasury and government agency securities	$	73,033	$	1,111	$	41,157	$	2,907	$	114,190	$	4,018
Municipal obligations		68,720		3,138		123,078		8,240		191,798		11,378
Residential mortgage-backed securities		7,389		196		1,950,817		463,486		1,958,206		463,682
Commercial mortgage-backed securities		83,732		1,723		2,757,618		407,156		2,841,350		408,879
Collateralized mortgage obligations		—		—		58,830		5,871		58,830		5,871
Corporate debt securities		—		—		19,607		3,393		19,607		3,393
Total	$	232,874	$	6,168	$	4,951,107	$	891,053	$	5,183,981	$	897,221

Available for Sale
December 31, 2022	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	$	102,607		754	$	8,258	$	1,592	$	110,865	$	2,346
Municipal obligations		192,334		3,981		—		—		192,334		3,981
Residential mortgage-backed securities		636,060		49,790		1,611,832		348,829		2,247,892		398,619
Commercial mortgage-backed securities		1,489,974		114,195		1,351,530		228,685		2,841,504		342,880
Collateralized mortgage obligations		41,703		3,275		28,884		2,967		70,587		6,242
Corporate debt securities		13,194		1,306		7,386		1,114		20,580		2,420
Total	$	2,475,872	$	173,301	$	3,007,890	$	583,187	$	5,483,762	$	756,488

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

Debt Securities Held to Maturity	Amortized		Fair
($ in thousands)	cost		value
Due in one year or less	$	103,187	$	100,661
Due after one year through five years		650,946		602,263
Due after five years through ten years		795,800		718,439
Due after ten years		1,178,012		1,008,924
Total held to maturity securities	$	2,727,945	$	2,430,287

Securities with Unrealized Losses

Held to maturity
September 30, 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	$	29,314	$	1,310	$	329,004	$	58,696	$	358,318	$	60,006
Municipal obligations		410,196		12,240		218,545		26,828		628,741		39,068
Residential mortgage-backed securities		—		—		584,996		88,902		584,996		88,902
Commercial mortgage-backed securities		—		—		826,028		107,231		826,028		107,231
Collateralized mortgage obligations		—		—		32,204		2,451		32,204		2,451
Total	$	439,510	$	13,550	$	1,990,777	$	284,108	$	2,430,287	$	297,658

Held to maturity
December 31, 2022	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	$	145,893	$	13,245	$	226,499	$	35,799	$	372,392	$	49,044
Municipal obligations		560,288		8,878		64,346		17,680		624,634		26,558
Residential mortgage-backed securities		391,146		30,515		270,800		42,017		661,946		72,532
Commercial mortgage-backed securities		697,827		56,899		163,653		30,312		861,480		87,211
Collateralized mortgage obligations		41,438		2,526		—		—		41,438		2,526
Total	$	1,836,592	$	112,063	$	725,298	$	125,808	$	2,561,890	$	237,871