Portfolio Loans - Summary of Portfolio Loans Individually Evaluated for Impairment by Category (Details) - Non-Covered Loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	$ 40,913	$ 26,047
Recorded Investment With No Allowance	9,798	5,823
Recorded Investment With Allowance	16,627	10,922
Total Recorded Investment	26,425	16,745
Related Allowance	2,567	4,453
Average Recorded Investment	29,540	15,573	$ 19,722
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	36,223	21,893
Recorded Investment With No Allowance	7,654	3,294
Recorded Investment With Allowance	14,924	9,656
Total Recorded Investment	22,578	12,950
Related Allowance	2,286	4,266
Average Recorded Investment	25,423	13,827
CRE - investor owned
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	2,988	553
Recorded Investment With No Allowance	811	398
Recorded Investment With Allowance	1,492	0
Total Recorded Investment	2,303	398
Related Allowance	247	0
Average Recorded Investment	2,457	277
CRE - owner occupied
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	237	847
Recorded Investment With No Allowance	213	472
Recorded Investment With Allowance	0	336
Total Recorded Investment	213	808
Related Allowance	0	109
Average Recorded Investment	231	691
Construction and land development
Financing Receivable, Impaired [Line Items]
Related Allowance	0	0
Residential real estate
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,464	2,425
Recorded Investment With No Allowance	1,120	1,659
Recorded Investment With Allowance	210	618
Total Recorded Investment	1,330	2,277
Related Allowance	33	52
Average Recorded Investment	1,428	778
Consumer and other
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1	329
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	1	312
Total Recorded Investment	1	312
Related Allowance	1	26
Average Recorded Investment	$ 1	$ 0

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 15
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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.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 14A
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