Loans and Allowance for Credit Losses on Loans - Changes in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Changes in the Allowance for Loan Losses
Beginning of period balance	$ 43,956	$ 45,444	$ 44,400	$ 23,285
Charge-offs	(65)	(598)	(433)	(1,736)
Recoveries	303	379	2,232	722
Net (charge-offs) recoveries	238	(219)	1,799	(1,014)
Provision for (recapture of) credit losses on loans	(514)	197	(2,519)	14,581
End of period balance	43,680	45,422	43,680	45,422
Decrease in the allowance of credit loss			521
Decrease in reserve for pooled loans			(199)
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	10,857	13,179	11,587
Charge-offs	(65)	(502)	(433)
Recoveries	263	343	1,191
Net (charge-offs) recoveries	198	(159)	758
Provision for (recapture of) credit losses on loans	(822)	(220)	(2,112)
End of period balance	10,233	12,800	10,233	12,800
CRE
Changes in the Allowance for Loan Losses
Beginning of period balance				10,453
Charge-offs				(1,637)
Recoveries				598
Net (charge-offs) recoveries				(1,039)
Provision for (recapture of) credit losses on loans				7,049
End of period balance		12,800		12,800
CRE \| 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	8,206	8,547	8,560	3,825
Recoveries	4		12	1
Net (charge-offs) recoveries	4		12	1
Provision for (recapture of) credit losses on loans	57	736	(305)	2,288
End of period balance	8,267	9,283	8,267	9,283
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	16,485	15,449	16,416	3,760
Provision for (recapture of) credit losses on loans	665	(124)	734	3,653
End of period balance	17,150	15,325	17,150	15,325
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	2,136	2,552	2,509	2,621
Recoveries		19	884	51
Net (charge-offs) recoveries		19	884	51
Provision for (recapture of) credit losses on loans	(112)	(27)	(1,369)	1,035
End of period balance	2,024	2,544	2,024	2,544
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	1,069	1,851	1,297	2,244
Recoveries	36	16	75	70
Net (charge-offs) recoveries	36	16	75	70
Provision for (recapture of) credit losses on loans	(94)	14	(361)	490
End of period balance	1,011	1,881	1,011	1,881
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	2,950	1,828	2,804	57
Provision for (recapture of) credit losses on loans	(61)	21	85	596
End of period balance	2,889	1,849	2,889	1,849
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	1,968	825	943	243
Provision for (recapture of) credit losses on loans	(97)	(46)	928	101
End of period balance	1,871	779	1,871	779
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	285	1,213	284	82
Charge-offs		(96)		(99)
Recoveries		1	70	2
Net (charge-offs) recoveries		(95)	70	(97)
Provision for (recapture of) credit losses on loans	(50)	(157)	(119)	(631)
End of period balance	$ 235	$ 961	$ 235	961
Consumer and other \| ASU 2016-03 - Topic 326
Changes in the Allowance for Loan Losses
Beginning of period balance				$ 1,607

Amount of increase (decrease) in reserve for pooled loans.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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