Loans and Allowance for Credit Losses on Loans - Changes in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in the Allowance for Loan Losses
Beginning of period balance	$ 44,703	$ 27,318	$ 23,285	$ 27,848
Charge-offs	(465)	(76)	(1,138)	(302)
Recoveries	92	129	343	886
Net (charge-offs) recoveries	(373)	53	(795)	584
Provision for credit losses on loans	1,114	(740)	14,384	(1,801)
End of period balance	45,444	26,631	45,444	26,631
ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			8,570
Commercial
Changes in the Allowance for Loan Losses
Beginning of period balance		15,557	10,453	17,061
Charge-offs		(76)		(302)
Recoveries		87		802
Net (charge-offs) recoveries		11		500
Provision for credit losses on loans		(334)		(2,327)
End of period balance		15,234		15,234
Real estate
Changes in the Allowance for Loan Losses
Beginning of period balance		11,671	12,750	10,671
Recoveries		42		84
Net (charge-offs) recoveries		42		84
Provision for credit losses on loans		(406)		552
End of period balance		11,307		11,307
Consumer
Changes in the Allowance for Loan Losses
Beginning of period balance		90	82	116
Provision for credit losses on loans				(26)
End of period balance		$ 90		$ 90
Commercial
Changes in the Allowance for Loan Losses
Beginning of period balance	12,801		10,453
Charge-offs	(465)		(1,135)
Recoveries	46		255
Net (charge-offs) recoveries	(419)		(880)
Provision for credit losses on loans	797		7,269
End of period balance	13,179		13,179
Commercial | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			(3,663)
CRE - owner occupied
Changes in the Allowance for Loan Losses
Beginning of period balance	7,737		3,825
Recoveries	1		1
Net (charge-offs) recoveries	1		1
Provision for credit losses on loans	809		1,552
End of period balance	8,547		8,547
CRE - owner occupied | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			3,169
CRE - non-owner occupied
Changes in the Allowance for Loan Losses
Beginning of period balance	15,645		3,760
Provision for credit losses on loans	(196)		3,777
End of period balance	15,449		15,449
CRE - non-owner occupied | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			7,912
Land and construction
Changes in the Allowance for Loan Losses
Beginning of period balance	2,603		2,621
Recoveries	13		32
Net (charge-offs) recoveries	13		32
Provision for credit losses on loans	(64)		1,062
End of period balance	2,552		2,552
Land and construction | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			(1,163)
Home equity
Changes in the Allowance for Loan Losses
Beginning of period balance	1,746		2,244
Recoveries	31		54
Net (charge-offs) recoveries	31		54
Provision for credit losses on loans	74		476
End of period balance	1,851		1,851
Home equity | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			(923)
Multi-family
Changes in the Allowance for Loan Losses
Beginning of period balance	1,622		57
Provision for credit losses on loans	206		575
End of period balance	1,828		1,828
Multi-family | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			1,196
Residential mortgages
Changes in the Allowance for Loan Losses
Beginning of period balance	708		243
Provision for credit losses on loans	117		147
End of period balance	825		825
Residential mortgages | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			435
Consumer and other
Changes in the Allowance for Loan Losses
Beginning of period balance	1,841		82
Charge-offs			(3)
Recoveries	1		1
Net (charge-offs) recoveries	1		(2)
Provision for credit losses on loans	(629)		(474)
End of period balance	$ 1,213		1,213
Consumer and other | ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance			$ 1,607