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Loans and Allowance for Credit Losses on Loans - CARES Act Narrative (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans at amortized cost	$ 2,002,767	$ 2,088,556
SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan	1,532
SBA PPP Round Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans funded during period | loan	1,060
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans at amortized cost	$ 423,646	498,408
Commercial loans | Commercial and industrial | SBA PPP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans at amortized cost	248,300	291,600
Financing receivable, unamortized loan fee	6,500	$ 5,400
Commercial loans | Commercial and industrial | SBA PPP Round Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in finance receivables	$ 136,000

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Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

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Amount of unamortized loan commitment, origination, and other fees (costs) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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