Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 166,209
Loans charged off	14,003
Recoveries of loans previously charged off	2,887
Current period net charge-offs	(11,116)
Provision for credit losses	44,029
Ending balance	257,471
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	58,349
Off-Balance Sheet
Allowance for Loan and Lease Losses [Roll Forward]
Provision for credit losses	3,800
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.

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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 recovery of financing receivables doubtful of collection that were previously charged off.

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

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