Securities (Tables)

6 Months Ended

Jun. 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

	June 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	$	10,036	$	—	$	972	$	9,064	$	420,857	$	3,781	$	5,340	$	419,298
Municipal obligations		213,486		338		3,080		210,744		304,536		13,184		3,562		314,158
Residential mortgage-backed securities		2,827,597		922		295,484		2,533,035		3,056,763		29,158		50,123		3,035,798
Commercial mortgage-backed securities		3,197,006		393		276,276		2,921,123		3,064,828		61,645		48,614		3,077,859
Collateralized mortgage obligations		86,809		—		3,771		83,038		119,046		1,837		—		120,883
Corporate debt securities		23,500		—		1,123		22,377		18,500		210		8		18,702
	$	6,358,434	$	1,653	$	580,706	$	5,779,381	$	6,984,530	$	109,815	$	107,647	$	6,986,698

Amortized Cost and Fair Value of Debt Securities Held to Maturity

	June 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	$	389,878	$	168	$	28,700	$	361,346	$	14,857	$	—	$	20	$	14,837
Municipal obligations		704,862		1,798		18,117		688,543		621,405		37,941		205		659,141
Residential mortgage-backed securities		702,905		—		43,366		659,539		268,907		682		1,499		268,090
Commercial mortgage-backed securities		900,776		—		46,664		854,112		603,156		28,679		669		631,166
Collateralized mortgage obligations		53,591		1		1,334		52,258		57,426		822		—		58,248
	$	2,752,012	$	1,967	$	138,181	$	2,615,798	$	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 six months ended June 30, 2022 and 2021. Net gains or losses are reflected in the "Securities transactions, net" line item on the Consolidated Statements of Income.

	Six Months EndedJune 30,
(in thousands)	2022			2021
Proceeds	$	73,219		$	198,681
Gross gains		—			1,649
Gross losses		87			1,316
Net 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	$	323	$	326
Due after one year through five years		825,767		803,642
Due after five years through ten years		2,932,193		2,674,994
Due after ten years		2,600,151		2,300,419
Total available for sale debt securities	$	6,358,434	$	5,779,381

Securities with Unrealized Losses

Available for Sale
June 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	$	9,064	$	972	$	—	$	—	$	9,064	$	972
Municipal obligations		180,505		3,080		—		—		180,505		3,080
Residential mortgage-backed securities		1,373,018		101,020		1,095,567		194,464		2,468,585		295,484
Commercial mortgage-backed securities		2,080,940		163,555		760,822		112,721		2,841,762		276,276
Collateralized mortgage obligations		83,038		3,771		—		—		83,038		3,771
Corporate debt securities		18,437		1,062		1,439		61		19,876		1,123
	$	3,745,002	$	273,460	$	1,857,828	$	307,246	$	5,602,830	$	580,706

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	$	11,035	$	11,005
Due after one year through five years		385,208		380,049
Due after five years through ten years		951,715		905,108
Due after ten years		1,404,054		1,319,636
Total held to maturity securities	$	2,752,012	$	2,615,798

Securities with Unrealized Losses

Held to maturity
June 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	$	274,813	$	21,723	$	66,290	$	6,977	$	341,103	$	28,700
Municipal obligations		418,484		10,931		39,761		7,186		458,245		18,117
Residential mortgage-backed securities		653,358		42,184		6,181		1,182		659,539		43,366
Commercial mortgage-backed securities		843,698		44,795		10,414		1,869		854,112		46,664
Collateralized mortgage obligations		51,451		1,334		—		—		51,451		1,334
	$	2,241,804	$	120,967	$	122,646	$	17,214	$	2,364,450	$	138,181

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