Securities (Tables)

9 Months Ended

Sep. 30, 2022

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, 2022								December 31, 2021
			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	$	44,481	$	—	$	2,194	$	42,287	$	420,857	$	3,781	$	5,340	$	419,298
Municipal obligations		207,941		71		10,147		197,865		304,536		13,184		3,562		314,158
Residential mortgage-backed securities		2,737,579		266		431,480		2,306,365		3,056,763		29,158		50,123		3,035,798
Commercial mortgage-backed securities		3,247,495		—		423,575		2,823,920		3,064,828		61,645		48,614		3,077,859
Collateralized mortgage obligations		81,383		—		6,294		75,089		119,046		1,837		—		120,883
Corporate debt securities		23,500		—		2,183		21,317		18,500		210		8		18,702
	$	6,342,379	$	337	$	875,873	$	5,466,843	$	6,984,530	$	109,815	$	107,647	$	6,986,698

Amortized Cost and Fair Value of Debt Securities Held to Maturity

	September 30, 2022								December 31, 2021
			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	$	407,097	$	—	$	48,703	$	358,394	$	14,857	$	—	$	20	$	14,837
Municipal obligations		701,353		23		37,888		663,488		621,405		37,941		205		659,141
Residential mortgage-backed securities		755,206		—		81,840		673,366		268,907		682		1,499		268,090
Commercial mortgage-backed securities		954,498		—		89,285		865,213		603,156		28,679		669		631,166
Collateralized mortgage obligations		48,194		—		2,575		45,619		57,426		822		—		58,248
	$	2,866,348	$	23	$	260,291	$	2,606,080	$	1,565,751	$	68,124	$	2,393	$	1,631,482

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, 2022 and 2021. 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)	2022			2021
Proceeds	$	73,219		$	198,681
Gross gains		—			1,649
Gross losses		87			1,316
Net gain (loss)	$	(87	)	$	333

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	$	101	$	101
Due after one year through five years		848,598		797,561
Due after five years through ten years		2,973,944		2,578,481
Due after ten years		2,519,736		2,090,700
Total available for sale debt securities	$	6,342,379	$	5,466,843

Securities with Unrealized Losses

Available for Sale
September 30, 2022	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	$	42,288	$	2,194	$	—	$	—	$	42,288	$	2,194
Municipal obligations		196,102		10,147		—		—		196,102		10,147
Residential mortgage-backed securities		763,658		76,195		1,535,412		355,285		2,299,070		431,480
Commercial mortgage-backed securities		1,803,019		204,268		1,020,901		219,307		2,823,920		423,575
Collateralized mortgage obligations		75,089		6,294		—		—		75,089		6,294
Corporate debt securities		19,376		2,124		1,441		59		20,817		2,183
	$	2,899,532	$	301,222	$	2,557,754	$	574,651	$	5,457,286	$	875,873

Available for Sale
December 31, 2021	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	$	198,318		2,305	$	63,534	$	3,035	$	261,852	$	5,340
Municipal obligations		43,021		2,372		25,126		1,190		68,147		3,562
Residential mortgage-backed securities		1,293,179		20,581		819,596		29,541		2,112,775		50,122
Commercial mortgage-backed securities		786,206		14,819		665,687		33,796		1,451,893		48,615
Collateralized mortgage obligations		—		—		—		—		—		—
Corporate debt securities		6,992		8		—		—		6,992		8
	$	2,327,716	$	40,085	$	1,573,943	$	67,562	$	3,901,659	$	107,647

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	$	10,000	$	9,890
Due after one year through five years		542,464		516,989
Due after five years through ten years		865,852		782,394
Due after ten years		1,448,032		1,296,807
Total held to maturity securities	$	2,866,348	$	2,606,080

Securities with Unrealized Losses

Held to maturity
September 30, 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	$	168,514	$	19,895	$	189,879	$	28,808	$	358,393	$	48,703
Municipal obligations		601,010		21,670		58,691		16,218		659,701		37,888
Residential mortgage-backed securities		574,671		65,187		98,695		16,653		673,366		81,840
Commercial mortgage-backed securities		810,889		79,651		54,324		9,634		865,213		89,285
Collateralized mortgage obligations		45,619		2,575		—		—		45,619		2,575
	$	2,200,703	$	188,978	$	401,589	$	71,313	$	2,602,292	$	260,291

Held to maturity
December 31, 2021	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	$	14,837	$	20	$	—	$	—	$	14,837	$	20
Municipal obligations		7,795		205		—		—		7,795		205
Residential mortgage-backed securities		253,661		1,499		—		—		253,661		1,499
Commercial mortgage-backed securities		56,366		205		11,837		464		68,203		669
Collateralized mortgage obligations		—		—		—		—		—		—
	$	332,659	$	1,929	$	11,837	$	464	$	344,496	$	2,393