Investment Securities (Investment Securities, At Fair Value) (Details) - USD ($) $ in Thousands		Mar. 31, 2024	Dec. 31, 2023
Investment Securities [Abstract]
Available for sale debt securities		$ 9,141,695	$ 9,684,760
Trading debt securities		56,716	28,830
Equity securities with a readily determinable fair value		5,864	5,723
Equity Securities without Readily Determinable Fair Value, Amount		6,988	6,978
Federal Reserve Bank Stock		35,267	35,166
Federal Home Loan Bank Stock		10,173	10,640
Private equity investments		183,706	176,667
Total investment securities	[1]	9,440,409	9,948,764
Interest Receivable, Current		$ 28,200	$ 28,900

[1] (1)Accrued interest receivable totaled $28.2 million and $28.9 million at March 31, 2024 and December 31, 2023, respectively, and was included within other assets on the consolidated balance sheets.