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Loans And Allowance For Loan Losses - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) contract	Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($) contract	Jan. 01, 2020 USD ($)	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, impaired, interest lost on nonaccrual loans	$ 11,100	$ 12,600
Loans and leases receivable, impaired, interest income recognized, change in present value attributable to passage of time	1,800	3,900
Loans pledged as collateral	14,190,000	15,050,000
Loans	39,311,958	38,252,984
Financing receivable, change in method, credit loss expense (reversal)		18,300
Transfers to held for sale		1,430,000
Financing receivable, allowance for credit loss	427,597	605,736	$ 281,402	$ 281,402	$ 250,555
Reserve for unfunded commitments	41,900			1,375
Allowance for credit losses	469,500	653,500		$ 282,777
Allowance for credit loss, decrease	$ 184,000
ACL to loans ratio	1.19%
Decrease in ACL to loans ratio	0.0052
Estimated unemployment rate	3.70%
Downside bias	43.00%
Financing receivable, allowance for credit loss, period increase (decrease) from increase in size of loan profile	$ 1,620,000
Financing receivable, purchase	$ 38,600
Allowance for credit loss, reasonable and supportable forecast period	2 years
Allowance for credit loss, straight-line basis historical period	1 year
Modifications, post-modification recorded investment	$ 48,932	76,615	$ 49,859
Unfunded Loan Commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss		$ 47,800
Troubled Debt Restructuring That Subsequently Defaulted
Accounts, Notes, Loans and Financing Receivable [Line Items]
Subsequent default, number of contracts | contract	8,000	7	4
Modifications, post-modification recorded investment	$ 978	$ 21,700	$ 326
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	19,561,161	19,520,168
Modifications, post-modification recorded investment	27,618	28,917	$ 28,793
Commercial and industrial | Small Business Administration (SBA), CARES Act, Paycheck Protection Program
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 399,600	$ 2,190,000

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