Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) - Non-Covered Loans $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 loan	Dec. 31, 2019 USD ($)
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	$ 41,473		$ 26,425
Recorded Investment With No Allowance	$ 27,284
Financing Receivable, Modifications, Number of Contracts \| loan	3	3
Nonaccrual	$ 36,867		26,096
Restructured, accruing	3,720		79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	886		250
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	31,938		22,578
Recorded Investment With No Allowance	$ 20,553
Financing Receivable, Modifications, Number of Contracts \| loan	1	0
Nonaccrual	$ 27,431		22,328
Restructured, accruing	3,642		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	865		250
Commercial - investor owned
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	2,389		2,303
Recorded Investment With No Allowance	1,677
Nonaccrual	2,389		2,303
Restructured, accruing	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0		0
Commercial - owner occupied
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	2,400		213
Recorded Investment With No Allowance	$ 1,403
Financing Receivable, Modifications, Number of Contracts \| loan	0	1
Nonaccrual	$ 2,400		213
Restructured, accruing	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0		0
Construction and land development
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	207
Recorded Investment With No Allowance	207
Nonaccrual	207
Restructured, accruing	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Residential real estate
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	4,499		1,330
Recorded Investment With No Allowance	$ 3,444
Financing Receivable, Modifications, Number of Contracts \| loan	2	2
Nonaccrual	$ 4,421		1,251
Restructured, accruing	78		79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0		0
Other
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	40		1
Recorded Investment With No Allowance	0
Nonaccrual	19		1
Restructured, accruing	0		0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	$ 21		$ 0

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Amount of financing receivable modified as troubled debt restructuring.

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