Securities (Securities Held to Maturity with Unrealized Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value	$ 50,829	$ 109,688
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses	30	1,291
Held to Maturity, Losses 12 months or longer, Fair Value	1,872,791	2,100,656
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	133,839	201,015
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	1,923,620	2,210,344
Held to Maturity, Total, Gross Unrealized Losses	133,869	202,306
U.S. Treasury And Government Agency Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value	0	27,660
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses	0	840
Held to Maturity, Losses 12 months or longer, Fair Value	328,482	321,154
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	32,414	45,036
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	328,482	348,814
Held to Maturity, Total, Gross Unrealized Losses	32,414	45,876
Municipal Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value	50,829	82,028
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses	30	451
Held to Maturity, Losses 12 months or longer, Fair Value	360,613	497,999
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	12,176	20,416
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	411,442	580,027
Held to Maturity, Total, Gross Unrealized Losses	12,206	20,867
Residential Mortgage-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value		0
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses		0
Held to Maturity, Losses 12 months or longer, Fair Value	477,676	511,531
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	38,581	61,525
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	477,676	511,531
Held to Maturity, Total, Gross Unrealized Losses	38,581	61,525
Commercial Mortgage-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value		0
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses		0
Held to Maturity, Losses 12 months or longer, Fair Value	685,944	745,750
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	50,025	72,854
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	685,944	745,750
Held to Maturity, Total, Gross Unrealized Losses	50,025	72,854
Collateralized Mortgage Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held to Maturity, Losses less than 12 months, Fair Value		0
Held to Maturity, Losses less than 12 months, Gross Unrealized Losses		0
Held to Maturity, Losses 12 months or longer, Fair Value	20,076	24,222
Held to Maturity, Losses 12 months or longer, Gross Unrealized Losses	643	1,184
Held To Maturity Securities Unrealized Loss Position Fair Value, Total	20,076	24,222
Held to Maturity, Total, Gross Unrealized Losses	$ 643	$ 1,184