Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 272,920	$ 166,209
Loans charged off	5,489	27,539
Recoveries of loans previously charged off	7,847	14,660
Total net (charge-offs) recoveries	2,358	12,879
Provision for credit losses	7,080	70,680
Ending balance	282,358	282,358
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0
Off-Balance Sheet
Allowance for Loan and Lease Losses [Roll Forward]
Provision for credit losses	$ 850	320
Off-Balance Sheet \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		$ 12,600

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

No definition available.

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Amount, after recovery, of writeoff of financing receivable, charged against allowance 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 increase in allowance for credit loss on financing receivable from recovery.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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