Loans - Summary of Portfolio Loans Individually Evaluated for Impairment by Category (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Loss	$ 43,822		$ 43,822	$ 43,476
Portfolio loans, net
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	1,960	$ 1,476
Unpaid Contractual Principal Balance	34,257		34,257	26,047
Recorded Investment With No Allowance	10,444		10,444	5,823
Recorded Investment With Allowance	9,398		9,398	10,922
Total Recorded Investment	19,842		19,842	16,745
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	2,599		2,599	4,453
Impaired Financing Receivable, Related Allowance	2,599		2,599	4,453
Average Recorded Investment			20,450	15,573
Financing Receivable, Allowance for Credit Loss, Writeoff	(1,890)	(2,250)
Financing Receivable, Allowance for Credit Loss, Recovery	920	424
Financing Receivable, Allowance for Credit Loss	42,935	41,945	42,935	42,295
Portfolio loans, net \| Commercial and industrial
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	1,781	1,445
Unpaid Contractual Principal Balance	28,835		28,835	21,893
Recorded Investment With No Allowance	6,826		6,826	3,294
Recorded Investment With Allowance	8,286		8,286	9,656
Total Recorded Investment	15,112		15,112	12,950
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	2,402		2,402	4,266
Impaired Financing Receivable, Related Allowance	2,402		2,402	4,266
Average Recorded Investment			16,728	13,827
Financing Receivable, Allowance for Credit Loss, Writeoff	(1,380)	(1,853)
Financing Receivable, Allowance for Credit Loss, Recovery	32	29
Financing Receivable, Allowance for Credit Loss	29,093	28,660	29,093	29,039
Portfolio loans, net \| Commercial - investor owned
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	364	769
Unpaid Contractual Principal Balance	1,948		1,948	553
Recorded Investment With No Allowance	459		459	398
Recorded Investment With Allowance	825		825	0
Total Recorded Investment	1,284		1,284	398
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	165		165	0
Impaired Financing Receivable, Related Allowance	165		165	0
Average Recorded Investment			1,460	277
Financing Receivable, Allowance for Credit Loss, Writeoff	(431)	(120)
Financing Receivable, Allowance for Credit Loss, Recovery	52	7
Financing Receivable, Allowance for Credit Loss	5,324	5,339	5,324	4,683
Portfolio loans, net \| Commercial - owner occupied
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	591	(431)
Unpaid Contractual Principal Balance	405		405	847
Recorded Investment With No Allowance	231		231	472
Recorded Investment With Allowance	155		155	336
Total Recorded Investment	386		386	808
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	9		9	109
Impaired Financing Receivable, Related Allowance	9		9	109
Average Recorded Investment			393	691
Financing Receivable, Allowance for Credit Loss, Writeoff	0	(36)
Financing Receivable, Allowance for Credit Loss, Recovery	6	2
Financing Receivable, Allowance for Credit Loss	4,371	3,774	4,371	4,239
Portfolio loans, net \| Construction and land development
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	(216)	(252)
Unpaid Contractual Principal Balance	0		0	0
Recorded Investment With No Allowance	0		0	0
Recorded Investment With Allowance	0		0	0
Total Recorded Investment	0		0	0
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0	0
Impaired Financing Receivable, Related Allowance	0		0	0
Average Recorded Investment			0	0
Financing Receivable, Allowance for Credit Loss, Writeoff	0	(45)
Financing Receivable, Allowance for Credit Loss, Recovery	489	9
Financing Receivable, Allowance for Credit Loss	1,972	1,699	1,972	1,987
Portfolio loans, net \| Residential real estate
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	(345)	(288)
Unpaid Contractual Principal Balance	3,069		3,069	2,425
Recorded Investment With No Allowance	2,928		2,928	1,659
Recorded Investment With Allowance	132		132	618
Total Recorded Investment	3,060		3,060	2,277
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	23		23	52
Impaired Financing Receivable, Related Allowance	23		23	52
Average Recorded Investment			1,869	778
Financing Receivable, Allowance for Credit Loss, Writeoff	(26)	(67)
Financing Receivable, Allowance for Credit Loss, Recovery	124	364
Financing Receivable, Allowance for Credit Loss	1,378	1,625	1,378	1,616
Portfolio loans, net \| Consumer and other
Financing Receivable, Impaired [Line Items]
Provision for Loan, Lease, and Other Losses	(215)	233
Unpaid Contractual Principal Balance	0		0	329
Recorded Investment With No Allowance	0		0	0
Recorded Investment With Allowance	0		0	312
Total Recorded Investment	0		0	312
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0	26
Impaired Financing Receivable, Related Allowance	0		0	26
Average Recorded Investment			0	0
Financing Receivable, Allowance for Credit Loss, Writeoff	(53)	(129)
Financing Receivable, Allowance for Credit Loss, Recovery	217	13
Financing Receivable, Allowance for Credit Loss	$ 797	$ 848	$ 797	$ 731

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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