Loans And Allowance For Loan Losses - Schedule Of Allowances For Loan Losses And Recorded Investment In Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 605,736	$ 281,402	$ 250,555
Charge-offs	(105,232)	(119,262)	(79,135)
Recoveries	27,444	24,550	21,523
Provision for (reversal of) loan losses	(100,351)	336,052	87,720
Transfer of unfunded commitment reserve			739
Ending balance	427,597	605,736	281,402
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		82,994
Ending balance			82,994
Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	605,736	364,396
Ending balance		605,736	364,396
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	229,555	145,782	133,123
Charge-offs	(59,457)	(76,260)	(49,572)
Recoveries	9,734	13,544	7,827
Provision for (reversal of) loan losses	8,532	148,799	53,665
Transfer of unfunded commitment reserve			739
Ending balance	188,364	229,555	145,782
Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(2,310)
Ending balance			(2,310)
Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	229,555	143,472
Ending balance		229,555	143,472
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	130,742	67,430	68,796
Charge-offs	(15,392)	(13,213)	(5,540)
Recoveries	7,444	2,857	8,618
Provision for (reversal of) loan losses	(25,034)	74,319	(4,444)
Transfer of unfunded commitment reserve			0
Ending balance	97,760	130,742	67,430
Commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(651)
Ending balance			(651)
Commercial real estate \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	130,742	66,779
Ending balance		130,742	66,779
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	245,439	68,190	48,636
Charge-offs	(30,383)	(29,789)	(24,023)
Recoveries	10,266	8,149	5,078
Provision for (reversal of) loan losses	(83,849)	112,934	38,499
Transfer of unfunded commitment reserve			0
Ending balance	141,473	245,439	68,190
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		85,955
Ending balance			85,955
Consumer \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 245,439	154,145
Ending balance		$ 245,439	$ 154,145

Transfer of unfunded commitment reserve

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of expense related to estimated loss from loan and lease transactions.

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