Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) - Non-Covered Loans $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 loan	Dec. 31, 2020 USD ($)
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	$ 42,252		$ 38,507
Nonaccrual loans with no allowance	15,067
Financing Receivable, Modifications, Number of Contracts \| loan		3
Nonaccrual	36,403		34,818
Restructured, accruing	3,042		3,559
Loans over 90 days past due and still accruing interest	2,807		130
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	24,844		21,770
Nonaccrual loans with no allowance	$ 10,215		8,316
Financing Receivable, Modifications, Number of Contracts \| loan	1
Nonaccrual	$ 19,082		18,158
Restructured, accruing	2,965		3,482
Loans over 90 days past due and still accruing interest	2,797		130
Commercial - investor owned
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	7,359		9,579
Nonaccrual loans with no allowance	441		716
Nonaccrual	7,359		9,579
Restructured, accruing	0		0
Loans over 90 days past due and still accruing interest	0		0
Commercial - owner occupied
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	5,885		2,940
Nonaccrual loans with no allowance	1,616		6,024
Nonaccrual	5,885		2,940
Restructured, accruing	0		0
Loans over 90 days past due and still accruing interest	0		0
Construction and land development
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	100
Nonaccrual loans with no allowance	100		0
Nonaccrual	100
Restructured, accruing	0
Loans over 90 days past due and still accruing interest	0
Residential real estate
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	4,038		4,189
Nonaccrual loans with no allowance	2,695		3,190
Financing Receivable, Modifications, Number of Contracts \| loan		2
Nonaccrual	3,961		4,112
Restructured, accruing	77		77
Loans over 90 days past due and still accruing interest	0		0
Other
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	26		29
Nonaccrual loans with no allowance	0		18,246
Nonaccrual	16		29
Restructured, accruing	0		0
Loans over 90 days past due and still accruing interest	$ 10		$ 0

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Amount of financing receivable modified as troubled debt restructuring.

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