Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($) loan	Dec. 31, 2018 USD ($)
Financing Receivable, Past Due [Line Items]
Restructured, accruing	$ 3,500
Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 19,842	$ 16,745
Financing Receivable, Modifications, Number of Contracts \| loan	3
Non-accrual	$ 15,659	16,520
Restructured, accruing	184	225
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	3,999
Impaired Financing Receivable, Related Allowance	2,599	4,453
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	2,599	4,453
Non-Covered Loans \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 15,112	12,950
Financing Receivable, Modifications, Number of Contracts \| loan	1
Non-accrual	$ 11,009	12,805
Restructured, accruing	104	145
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	3,999
Impaired Financing Receivable, Related Allowance	2,402	4,266
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	2,402	4,266
Non-Covered Loans \| Commercial - investor owned
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	1,284	398
Non-accrual	1,284	398
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Impaired Financing Receivable, Related Allowance	165	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	165	0
Non-Covered Loans \| Commercial - owner occupied
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	386	808
Non-accrual	386	808
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Impaired Financing Receivable, Related Allowance	9	109
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	9	109
Non-Covered Loans \| Construction and land development
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Non-accrual	0	0
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Impaired Financing Receivable, Related Allowance	0	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Non-Covered Loans \| Residential real estate
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 3,060	2,277
Financing Receivable, Modifications, Number of Contracts \| loan	2
Non-accrual	$ 2,980	2,197
Restructured, accruing	80	80
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Impaired Financing Receivable, Related Allowance	23	52
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	23	52
Non-Covered Loans \| Consumer and other
Financing Receivable, Past Due [Line Items]
Impaired Financing Receivable, Recorded Investment	0	312
Non-accrual	0	312
Restructured, accruing	0	0
Impaired Financing Receivables, Recorded Investment, 90 Days Past Due and Still Accruing	0
Impaired Financing Receivable, Related Allowance	0	26
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 0	$ 26

The balance of impaired financing receivables greater than 90 days past due that are still accruing interest.

No definition available.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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-Publisher FASB
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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
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