Loans - Summary of Portfolio Loans Individually Evaluated for Impairment by Category (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Financing receivable, allowance for credit loss	$ 43,288
Portfolio loans, net
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		$ 27,284		$ 27,284
Total Recorded Investment		41,473		41,473			$ 26,425
Financing Receivable, Allowance for Credit Loss, Writeoff		(3,664)		(3,968)
Financing Receivable, Allowance for Credit Loss, Recovery		3,356		4,157
Financing receivable, allowance for credit loss	69,995	110,270		110,270		$ 92,187	43,288
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	28,387
Provision for credit losses	1,680	(18,400)	$ (1,700)	(40,100)	$ (3,200)
Portfolio loans, net | Commercial and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		20,553		20,553
Total Recorded Investment		31,938		31,938			22,578
Financing Receivable, Allowance for Credit Loss, Writeoff		(3,303)		(3,366)
Financing Receivable, Allowance for Credit Loss, Recovery		293		797
Financing receivable, allowance for credit loss	33,949	50,139		50,139		45,981	27,455
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	6,494
Provision for credit losses	0
Portfolio loans, net | Commercial - investor owned
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		1,677		1,677
Total Recorded Investment		2,389		2,389			2,303
Financing Receivable, Allowance for Credit Loss, Writeoff		(224)		(226)
Financing Receivable, Allowance for Credit Loss, Recovery		2,752		2,766
Financing receivable, allowance for credit loss	16,656	25,019		25,019		19,892	5,935
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	10,726
Provision for credit losses	5
Portfolio loans, net | Commercial - owner occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		1,403		1,403
Total Recorded Investment		2,400		2,400			213
Financing Receivable, Allowance for Credit Loss, Writeoff		0		0
Financing Receivable, Allowance for Credit Loss, Recovery		11		80
Financing receivable, allowance for credit loss	7,414	11,088		11,088		9,477	4,873
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	2,598
Provision for credit losses	57
Portfolio loans, net | Construction and land development
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		207		207
Total Recorded Investment		207		207
Financing Receivable, Allowance for Credit Loss, Writeoff		0		(31)
Financing Receivable, Allowance for Credit Loss, Recovery		29		69
Financing receivable, allowance for credit loss	7,577	15,962		15,962		9,895	2,611
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	5,183
Provision for credit losses	217
Portfolio loans, net | Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		3,444		3,444
Total Recorded Investment		4,499		4,499			1,330
Financing Receivable, Allowance for Credit Loss, Writeoff		(32)		(154)
Financing Receivable, Allowance for Credit Loss, Recovery		226		383
Financing receivable, allowance for credit loss	3,349	6,333		6,333		5,395	1,280
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	3,470
Provision for credit losses	1,401
Portfolio loans, net | Other
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		0		0
Total Recorded Investment		40		40			1
Financing Receivable, Allowance for Credit Loss, Writeoff		(105)		(191)
Financing Receivable, Allowance for Credit Loss, Recovery		45		62
Financing receivable, allowance for credit loss	1,050	$ 1,729		$ 1,729		$ 1,547	$ 1,134
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	(84)
Provision for credit losses	$ 0