Securities (Amortized Cost and Fair Value of Debt Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Debt Securities Available for Sale, Due in one year or less, Amortized Cost	$ 31,863
Debt Securities Available for Sale, Due after one year through five years, Amortized Cost	971,094
Debt Securities Available for Sale, Due after five years through ten years, Amortized Cost	2,336,366
Debt Securities Available for Sale, Due after ten years, Amortized Cost	2,505,722
Securities Available for Sale, Amortized Cost	5,845,045	$ 5,774,133
Debt Securities Available for Sale, Due in one year or less, Fair Value	31,963
Debt Securities Available for Sale, Due after one year through five years, Fair Value	950,634
Debt Securities Available for Sale, Due after five years through ten years, Fair Value	2,146,246
Debt Securities Available for Sale, Due after ten years, Fair Value	2,205,685
Total available for sale debt securities, Fair Value	5,334,528	5,161,491
Debt Securities Held to Maturity, Due in one year or less, Amortized Cost	110,832
Debt Securities Held to Maturity, Due after one year through five years, Amortized Cost	764,462
Debt Securities Held to Maturity, Due after five years through ten years, Amortized Cost	536,603
Debt Securities Held to Maturity, Due after ten years, Amortized Cost	948,544
Securities Held to Maturity, Gross Amortized Cost	2,360,441	2,435,663
Debt Securities Held to Maturity, Due in one year or less, Fair Value	110,453
Debt Securities Held to Maturity, Due after one year through five years, Fair Value	733,857
Debt Securities Held to Maturity, Due after five years through ten years, Fair Value	505,119
Debt Securities Held to Maturity, Due after ten years, Fair Value	845,198
Total held to maturity securities, Fair Value	$ 2,194,627	$ 2,233,526