Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) - Non-Covered Loans $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($)
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	$ 37,204	$ 26,425
Recorded Investment With No Allowance	$ 24,905
Financing Receivable, Modifications, Number of Contracts \| loan	3
Nonaccrual	$ 33,268	26,096
Restructured, accruing	3,810	79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	126	250
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	26,531	22,578
Recorded Investment With No Allowance	$ 17,915
Financing Receivable, Modifications, Number of Contracts \| loan	1
Nonaccrual	$ 22,729	22,328
Restructured, accruing	3,731	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	71	250
Commercial - investor owned
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	4,115	2,303
Recorded Investment With No Allowance	2,576
Nonaccrual	4,115	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	2,110	213
Recorded Investment With No Allowance	1,114
Nonaccrual	2,110	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	214
Recorded Investment With No Allowance	214
Nonaccrual	214
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	4,154	1,330
Recorded Investment With No Allowance	$ 3,086
Financing Receivable, Modifications, Number of Contracts \| loan	2
Nonaccrual	$ 4,075	1,251
Restructured, accruing	79	79
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Consumer and other
Financing Receivable, Past Due [Line Items]
Total Recorded Investment	80	1
Recorded Investment With No Allowance	0
Nonaccrual	25	1
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	$ 55	$ 0

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