LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	$ 97,991	$ 99,475	$ 96,270	$ 106,094
Charge-offs	(7,685)	(1,598)	(15,621)	(7,645)
Recoveries	1,913	1,139	2,952	4,561
Provision for Credit Losses	8,000	5	17,019	(3,989)
Balance at End of Period	100,219	99,021	100,219	99,021
Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		(401)
Construction and commercial multifamily \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	1,536	2,505	1,227	3,206
Charge-offs	(1)	0	(1)	0
Recoveries	0	0	0	0
Provision for Credit Losses	18	(795)	327	(1,496)
Balance at End of Period	1,553	1,710	1,553	1,710
Construction and commercial multifamily \| Construction \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		0
Construction and commercial multifamily \| Commercial multifamily
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	1,698	5,771	1,810	6,120
Charge-offs	0	0	0	0
Recoveries	0	0	6	0
Provision for Credit Losses	368	(1,150)	250	(1,499)
Balance at End of Period	2,066	4,621	2,066	4,621
Construction and commercial multifamily \| Commercial multifamily \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		0
Commercial real estate \| Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	10,278	11,498	10,739	12,752
Charge-offs	(394)	(298)	(464)	(428)
Recoveries	596	97	641	306
Provision for Credit Losses	(137)	(609)	(597)	(1,942)
Balance at End of Period	10,343	10,688	10,343	10,688
Commercial real estate \| Commercial real estate owner occupied \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		24
Commercial real estate \| Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	33,408	25,814	30,724	32,106
Charge-offs	0	0	0	(4,884)
Recoveries	81	46	175	1,312
Provision for Credit Losses	2,833	305	5,423	(2,369)
Balance at End of Period	36,322	26,165	36,322	26,165
Commercial real estate \| Commercial real estate non-owner occupied \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		0
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	20,164	22,949	18,743	22,584
Charge-offs	(4,595)	(752)	(10,627)	(1,405)
Recoveries	815	584	1,119	1,872
Provision for Credit Losses	2,357	133	9,529	(137)
Balance at End of Period	18,741	22,914	18,741	22,914
Commercial and industrial \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		(23)
Residential real estate \| Residential real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	17,590	17,816	18,666	22,406
Charge-offs	(210)	(216)	(240)	(380)
Recoveries	76	199	463	587
Provision for Credit Losses	762	(1,389)	(673)	(6,203)
Balance at End of Period	18,218	16,410	18,218	16,410
Residential real estate \| Residential real estate \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		2
Consumer loans \| Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	2,320	3,303	2,173	4,006
Charge-offs	(7)	0	(18)	0
Recoveries	132	112	159	246
Provision for Credit Losses	127	(587)	258	(1,424)
Balance at End of Period	2,572	2,828	2,572	2,828
Consumer loans \| Home equity \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	0		0
Consumer loans \| Consumer other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	10,997	9,819	12,188	2,914
Charge-offs	(2,478)	(332)	(4,271)	(548)
Recoveries	213	101	389	238
Provision for Credit Losses	1,672	4,097	2,502	11,081
Balance at End of Period	10,404	$ 13,685	10,404	$ 13,685
Consumer loans \| Consumer other \| Impact of ASU No. 2022-02 Adoption
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at Beginning of Period	$ 0		$ (404)

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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