Securities (Amortized Cost and Fair Value of Debt Securities Held to Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	$ 2,197,611	$ 2,435,663
Securities Held to Maturity, Gross Unrealized Gains	849	169
Securities Held to Maturity, Gross Unrealized Losses	133,869	202,306
Securities Held to Maturity, Fair Value	2,064,591	2,233,526
U.S. Treasury And Government Agency Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	379,390	394,689
Securities Held to Maturity, Gross Unrealized Gains	230
Securities Held to Maturity, Gross Unrealized Losses	32,414	45,876
Securities Held to Maturity, Fair Value	347,206	348,813
Municipal Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	545,276	623,907
Securities Held to Maturity, Gross Unrealized Gains	619	169
Securities Held to Maturity, Gross Unrealized Losses	12,206	20,867
Securities Held to Maturity, Fair Value	533,689	603,209
Residential Mortgage-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	516,257	573,057
Securities Held to Maturity, Gross Unrealized Losses	38,581	61,525
Securities Held to Maturity, Fair Value	477,676	511,532
Commercial Mortgage-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	735,969	818,604
Securities Held to Maturity, Gross Unrealized Losses	50,025	72,854
Securities Held to Maturity, Fair Value	685,944	745,750
Collateralized Mortgage Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities Held to Maturity, Gross Amortized Cost	20,719	25,406
Securities Held to Maturity, Gross Unrealized Losses	643	1,184
Securities Held to Maturity, Fair Value	$ 20,076	$ 24,222