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Loans and Allowance for Credit Losses - Non-TDR Loan Modifications due to COVID-19 (Details) - CARES Act Modification $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($) deferral	Dec. 31, 2020 USD ($)
Financing Receivable, Modification [Line Items]
Deferrals Balance	$ 20,171	$ 63,902
Number of Deferrals | deferral	187
Commercial and commercial real estate
Financing Receivable, Modification [Line Items]
Deferrals Balance	$ 16,641	53,823
Number of Deferrals | deferral	34
Second deferrals between 90 and 180 days, amount	$ 4,200
Residential real estate
Financing Receivable, Modification [Line Items]
Deferrals Balance	$ 767	1,855
Number of Deferrals | deferral	2
Second deferrals between 90 and 180 days, amount	$ 100
Consumer credit
Financing Receivable, Modification [Line Items]
Deferrals Balance	$ 2,763	$ 8,224
Number of Deferrals | deferral	151
Second deferrals between 90 and 180 days, amount	$ 400

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