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Loans - Summary of Portfolio Loans Individually Evaluated for Impairment by Category (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 01, 2020	Mar. 31, 2020	Mar. 31, 2019	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		$ 24,905
Total Recorded Investment		37,204		$ 26,425
Financing Receivable, Allowance for Credit Loss, Writeoff		(304)
Financing Receivable, Allowance for Credit Loss, Recovery		801
Financing receivable, allowance for credit loss	69,995	92,187		43,288
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	28,387
Provision for credit losses	1,680	(21,695)	$ (1,500)
Portfolio loans, net \| Commercial and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		17,915
Total Recorded Investment		26,531		22,578
Financing Receivable, Allowance for Credit Loss, Writeoff		(63)
Financing Receivable, Allowance for Credit Loss, Recovery		504
Financing receivable, allowance for credit loss	33,949	45,981		27,455
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	6,494
Provision for credit losses	0	(11,591)
Portfolio loans, net \| Commercial - investor owned
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		2,576
Total Recorded Investment		4,115		2,303
Financing Receivable, Allowance for Credit Loss, Writeoff		(2)
Financing Receivable, Allowance for Credit Loss, Recovery		14
Financing receivable, allowance for credit loss	16,656	19,892		5,935
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	10,726
Provision for credit losses	5	(3,224)
Portfolio loans, net \| Commercial - owner occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		1,114
Total Recorded Investment		2,110		213
Financing Receivable, Allowance for Credit Loss, Writeoff		0
Financing Receivable, Allowance for Credit Loss, Recovery		69
Financing receivable, allowance for credit loss	7,414	9,477		4,873
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	2,598
Provision for credit losses	57	(1,994)
Portfolio loans, net \| Construction and land development
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		214
Total Recorded Investment		214
Financing Receivable, Allowance for Credit Loss, Writeoff		(31)
Financing Receivable, Allowance for Credit Loss, Recovery		40
Financing receivable, allowance for credit loss	7,577	9,895		2,611
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	5,183
Provision for credit losses	217	(2,309)
Portfolio loans, net \| Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		3,086
Total Recorded Investment		4,154		1,330
Financing Receivable, Allowance for Credit Loss, Writeoff		(122)
Financing Receivable, Allowance for Credit Loss, Recovery		157
Financing receivable, allowance for credit loss	3,349	5,395		1,280
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	3,470
Provision for credit losses	1,401	(2,011)
Portfolio loans, net \| Consumer and other
Financing Receivable, Impaired [Line Items]
Recorded Investment With No Allowance		0
Total Recorded Investment		80		1
Financing Receivable, Allowance for Credit Loss, Writeoff		(86)
Financing Receivable, Allowance for Credit Loss, Recovery		17
Financing receivable, allowance for credit loss	1,050	1,547		$ 1,134
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	(84)
Provision for credit losses	$ 0	$ (566)