Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands		Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Investment Securities [Abstract]
Available for sale debt securities		$ 9,167,681		$ 9,684,760
Trading debt securities		42,645		28,830
Equity securities with a readily determinable fair value		48,262		5,723
Equity Securities without Readily Determinable Fair Value, Amount		8,853	$ 65,780	6,978
Federal Reserve Bank Stock		35,451		35,166
Federal Home Loan Bank Stock		10,119		10,640
Private equity investments		170,973		176,667
Total investment securities	[1]	9,483,984		9,948,764
Interest Receivable, Current		$ 29,700		$ 28,900

[1] (1)Accrued interest receivable totaled $29.7 million and $28.9 million at September 30, 2024 and December 31, 2023, respectively, and was included within other assets on the consolidated balance sheets.