Loans Held for Sale, Loans and Allowance for Credit Losses - Summary of Loans Held for Sale by Portfolio Segment at Lower of Amortized Cost or Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Loans held for sale	$ 38,221	$ 87,649
Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Loans held for sale	33,023	34,767
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Loans held for sale	2,913	49,894
Consumer
Accounts Notes And Loans Receivable [Line Items]
Loans held for sale	$ 2,285	$ 2,988