Allowance for Credit Losses - Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	$ 71,124	$ 40,003
Charge-offs	(1,270)	(483)
Recoveries	206	141
Provision for credit loss - loans	(2,808)	9,223
Balance at end of the period	67,252	48,884
Commercial, secured by real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period		28,950
Charge-offs		(169)
Recoveries		26
Provision for credit loss - loans		5,986
Balance at end of the period		34,793
Non owner occupied commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	25,910
Charge-offs	(593)
Recoveries	1
Provision for credit loss - loans	(1,438)
Balance at end of the period	23,880
Owner occupied commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	3,955
Charge-offs	(78)
Recoveries	8
Provision for credit loss - loans	118
Balance at end of the period	4,003
Multifamily
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	7,253
Charge-offs	0
Recoveries	0
Provision for credit loss - loans	255
Balance at end of the period	7,508
Non owner occupied residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	3,321
Charge-offs	(208)
Recoveries	2
Provision for credit loss - loans	(232)
Balance at end of the period	2,883
Commercial, industrial and other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	13,665	3,289
Charge-offs	(265)	0
Recoveries	44	30
Provision for credit loss - loans	(1,305)	2,170
Balance at end of the period	12,139	5,489
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	786	2,672
Charge-offs	0	0
Recoveries	25	32
Provision for credit loss - loans	318	640
Balance at end of the period	1,129	3,344
Equipment finance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	6,552	957
Charge-offs	(94)	(84)
Recoveries	11	14
Provision for credit loss - loans	(205)	370
Balance at end of the period	6,264	1,257
Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	3,623	1,725
Charge-offs	0	(116)
Recoveries	58	20
Provision for credit loss - loans	100	(29)
Balance at end of the period	3,781	1,600
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of the period	6,059	2,410
Charge-offs	(32)	(114)
Recoveries	57	19
Provision for credit loss - loans	(419)	86
Balance at end of the period	$ 5,665	$ 2,401