Investment Securities (Narrative) (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Equity securities without readily determinable fair values	$ 43,800,000	$ 37,500,000
Upward adjustments of equity securities without readily determinable fair values	0	0	$ 401,000
Downward adjustments of equity securities without readily determinable fair values	0	0	0
Impairment of equity securities without readily determinable fair values	12,158,000	2,415,000	2,995,000
Income tax (benefit) expense	190,873,000	171,645,000	96,791,000
Pledged securities	$ 2,800,000,000	2,600,000,000
Number of securities by a single non-government sponsored issuer exceeding 10% of shareholders' equity | security	0
Investment securities
Debt Securities, Available-for-sale [Line Items]
Income tax (benefit) expense	$ (5,400,000)	$ (282,000)	$ (513,000)