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Loans and Allowance for Credit Losses - CARES Act Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	$ 2,121,772	$ 2,088,556
SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan	2,513
SBA PPP Round Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans funded during period | loan	841
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	$ 545,069	498,408
Commercial loans | Commercial and industrial | SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at amortized cost	365,000	291,600
Financing receivable, unamortized loan fee	8,000	$ 5,400
Commercial loans | Commercial and industrial | SBA PPP Round Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in finance receivables	$ 119,500

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