Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 loan	Dec. 31, 2019 USD ($)
Financing Receivable, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts \| loan	3
Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	$ 39,623	$ 39,623		$ 26,425
Recorded Investment With No Allowance	16,605	$ 16,605
Financing Receivable, Modifications, Number of Contracts \| loan		6	3
Nonaccrual	35,037	$ 35,037		26,096
Restructured, accruing	3,635	3,635		79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	951	951		250
Non-Covered Loans \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	23,586	23,586		22,578
Recorded Investment With No Allowance	10,208	$ 10,208
Financing Receivable, Modifications, Number of Contracts \| loan		3	0
Nonaccrual	19,141	$ 19,141		22,328
Restructured, accruing	3,557	3,557		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	888	888		250
Non-Covered Loans \| Commercial - investor owned
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	9,850	9,850		2,303
Recorded Investment With No Allowance	1,440	1,440
Nonaccrual	9,850	9,850		2,303
Restructured, accruing	0	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0	0		0
Non-Covered Loans \| Commercial - owner occupied
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	1,511	1,511		213
Recorded Investment With No Allowance	1,511	$ 1,511
Financing Receivable, Modifications, Number of Contracts \| loan		0	1
Nonaccrual	1,511	$ 1,511		213
Restructured, accruing	0	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0	0		0
Non-Covered Loans \| Construction and land development
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	200	200
Recorded Investment With No Allowance	200	200
Nonaccrual	200	200
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Non-Covered Loans \| Residential real estate
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	4,394	4,394		1,330
Recorded Investment With No Allowance	3,246	$ 3,246
Financing Receivable, Modifications, Number of Contracts \| loan		3	2
Nonaccrual	4,316	$ 4,316		1,251
Restructured, accruing	78	78		79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0	0		0
Non-Covered Loans \| Other
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	82	82		1
Recorded Investment With No Allowance	0	0
Nonaccrual	19	19		1
Restructured, accruing	0	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	$ 63	$ 63		$ 0

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