LOANS AND CREDIT QUALITY - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Allowance for credit losses by loan portfolio
Beginning balance	$ 37,355	$ 59,897	$ 37,355	$ 59,897	$ 37,944	$ 47,123	$ 64,047	$ 64,294
Charge-offs	(682)	(79)	(726)	(205)
Recoveries	309	74	397	324
Provision	(216)	(4,145)	(9,439)	(4,516)
Ending balance	37,355	59,897	37,355	59,897
Commercial loans | Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	24,851	25,544	24,851	25,544	20,086	21,486	28,162	27,935
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	4,765	(2,618)	3,365	(2,391)
Ending balance	24,851	25,544	24,851	25,544
Commercial loans | Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	4,670	21,392	4,670	21,392	10,446	17,279	22,371	22,037
Charge-offs	(649)	0	(660)	0
Recoveries	45	24	69	98
Provision	(5,172)	(1,003)	(12,018)	(743)
Ending balance	4,670	21,392	4,670	21,392
Commercial loans | Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	2,180	9,077	2,180	9,077	2,294	7,509	9,218	8,845
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(114)	(141)	(5,329)	232
Ending balance	2,180	9,077	2,180	9,077
Commercial loans | Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	10,074	7,245	10,074	7,245	8,427	5,854	6,969	6,072
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	1,647	276	4,220	1,173
Ending balance	10,074	7,245	10,074	7,245
Commercial loans | Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	566	500	566	500	456	507	3,936	4,903
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	110	(3,436)	59	(4,403)
Ending balance	566	500	566	500
Commercial loans | CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	185	2,022	185	2,022	184	150	1,908	1,670
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	1	114	35	352
Ending balance	185	2,022	185	2,022
Commercial loans | Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	10,687	5,653	10,687	5,653	7,735	6,411	5,007	5,130
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	2,952	646	4,276	523
Ending balance	10,687	5,653	10,687	5,653
Commercial loans | Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	1,159	1,047	1,159	1,047	990	1,055	1,124	1,315
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	169	(77)	104	(268)
Ending balance	1,159	1,047	1,159	1,047
Commercial loans | Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	1,092	5,518	1,092	5,518	3,536	5,006	5,266	4,994
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(2,444)	252	(3,914)	524
Ending balance	1,092	5,518	1,092	5,518
Commercial loans | Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	3,578	15,874	3,578	15,874	6,910	12,273	17,105	17,043
Charge-offs	(649)	0	(660)	0
Recoveries	45	24	69	98
Provision	(2,728)	(1,255)	(8,104)	(1,267)
Ending balance	3,578	15,874	3,578	15,874
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	7,834	12,961	7,834	12,961	7,412	8,358	13,514	14,322
Charge-offs	(33)	(79)	(66)	(205)
Recoveries	264	50	328	226
Provision	191	(524)	(786)	(1,382)
Ending balance	7,834	12,961	7,834	12,961
Consumer loans | Single family
Allowance for credit losses by loan portfolio
Beginning balance	4,027	7,163	4,027	7,163	3,762	4,394	6,735	6,906
Charge-offs	0	(44)	0	(114)
Recoveries	136	2	140	122
Provision	129	470	(507)	249
Ending balance	4,027	7,163	4,027	7,163
Consumer loans | Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,807	5,798	3,807	5,798	$ 3,650	$ 3,964	$ 6,779	$ 7,416
Charge-offs	(33)	(35)	(66)	(91)
Recoveries	128	48	188	104
Provision	62	(994)	(279)	(1,631)
Ending balance	$ 3,807	$ 5,798	$ 3,807	$ 5,798