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LOANS AND CREDIT QUALITY - Amortized Cost in Loans Based Upon Year of Origination and Risk Rating (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Total loan and lease receivables before allowance for credit losses	$ 14,568,795		$ 14,568,795		$ 9,643,497
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Total	12,803	$ 14,572	34,969	$ 46,034
Commercial and industrial
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	18,428		18,428		28,334
Financing receivable, year two	45,255		45,255		113,024
Financing receivable, year three	55,412		55,412		41,276
Financing receivable, year four	65,630		65,630		23,371
Financing receivable, more than four years					63,129
Financing receivable, year five	29,470		29,470
Financing receivable, more than five years	102,055		102,055
Revolving Loans Amortized Cost Basis	230,176		230,176		140,906
Revolving Loans Converted to Term	885		885		0
Total loan and lease receivables before allowance for credit losses	547,311		547,311		410,040
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Financing receivable, year one, Gross charge-offs			0		0
Financing receivable, year two, Gross charge-offs			383		191
Financing receivable, year three, Gross charge-offs			100		95
Financing receivable, year four, Gross charge-offs			0		2
Financing receivable, Gross charge-offs more than four years					127
Financing receivable, year five, Gross charge-offs			16
Financing receivable, more than five years, Gross charge-offs			0
Revolving Loans Amortized Cost Basis			206		806
Revolving Loans Converted to Term			0		0
Total	484	313	705	525	1,221
Commercial and industrial | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	18,360		18,360		28,334
Financing receivable, year two	44,507		44,507		113,024
Financing receivable, year three	55,030		55,030		41,271
Financing receivable, year four	32,011		32,011		23,098
Financing receivable, more than four years					55,675
Financing receivable, year five	27,792		27,792
Financing receivable, more than five years	83,171		83,171
Revolving Loans Amortized Cost Basis	226,292		226,292		140,905
Revolving Loans Converted to Term	885		885		0
Total loan and lease receivables before allowance for credit losses	488,048		488,048		402,307
Commercial and industrial | Special mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	114		114		0
Financing receivable, year three	0		0		0
Financing receivable, year four	493		493		107
Financing receivable, more than four years					789
Financing receivable, year five	1,078		1,078
Financing receivable, more than five years	2,932		2,932
Revolving Loans Amortized Cost Basis	479		479		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	5,096		5,096		896
Commercial and industrial | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	68		68		0
Financing receivable, year two	634		634		0
Financing receivable, year three	382		382		5
Financing receivable, year four	33,126		33,126		166
Financing receivable, more than four years					6,665
Financing receivable, year five	600		600
Financing receivable, more than five years	15,952		15,952
Revolving Loans Amortized Cost Basis	3,405		3,405		1
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	54,167		54,167		6,837
Commercial and industrial | Doubtful
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	0		0		0
Commercial real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Total loan and lease receivables before allowance for credit losses	5,448,374		5,448,374		2,794,581
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Total	250	$ 0	250	$ 0
Commercial real estate | Multifamily
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	52,711		52,711		183,739
Financing receivable, year two	180,574		180,574		383,108
Financing receivable, year three	465,800		465,800		777,706
Financing receivable, year four	2,325,986		2,325,986		690,644
Financing receivable, more than four years					737,915
Financing receivable, year five	1,231,541		1,231,541
Financing receivable, more than five years	1,153,631		1,153,631
Revolving Loans Amortized Cost Basis	38,131		38,131		21,469
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	5,448,374		5,448,374		2,794,581
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Financing receivable, year one, Gross charge-offs			0		0
Financing receivable, year two, Gross charge-offs			0		0
Financing receivable, year three, Gross charge-offs			0		0
Financing receivable, year four, Gross charge-offs			0		0
Financing receivable, Gross charge-offs more than four years					0
Financing receivable, year five, Gross charge-offs			0
Financing receivable, more than five years, Gross charge-offs			0
Revolving Loans Amortized Cost Basis			0		0
Revolving Loans Converted to Term			0		0
Total			0		0
Commercial real estate | Multifamily | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	52,711		52,711		183,739
Financing receivable, year two	180,574		180,574		383,108
Financing receivable, year three	459,247		459,247		777,706
Financing receivable, year four	2,212,986		2,212,986		690,644
Financing receivable, more than four years					736,585
Financing receivable, year five	1,183,086		1,183,086
Financing receivable, more than five years	1,094,711		1,094,711
Revolving Loans Amortized Cost Basis	38,131		38,131		21,469
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	5,221,446		5,221,446		2,793,251
Commercial real estate | Multifamily | Special mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	49,972		49,972		0
Financing receivable, more than four years					0
Financing receivable, year five	24,099		24,099
Financing receivable, more than five years	43,439		43,439
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	117,510		117,510		0
Commercial real estate | Multifamily | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	6,553		6,553		0
Financing receivable, year four	63,028		63,028		0
Financing receivable, more than four years					1,330
Financing receivable, year five	24,356		24,356
Financing receivable, more than five years	15,481		15,481
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	109,418		109,418		1,330
Commercial real estate | Multifamily | Doubtful
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	0		0		0
Commercial real estate | Non-owner occupied
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	3,057		3,057		15,127
Financing receivable, year two	13,810		13,810		37,938
Financing receivable, year three	36,000		36,000		347,939
Financing receivable, year four	385,373		385,373		95,368
Financing receivable, more than four years					1,118,968
Financing receivable, year five	138,952		138,952
Financing receivable, more than five years	1,245,114		1,245,114
Revolving Loans Amortized Cost Basis	41,734		41,734		42,257
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	1,864,040		1,864,040		1,657,597
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Financing receivable, year one, Gross charge-offs			0		0
Financing receivable, year two, Gross charge-offs			0		0
Financing receivable, year three, Gross charge-offs			0		0
Financing receivable, year four, Gross charge-offs			0		0
Financing receivable, Gross charge-offs more than four years					0
Financing receivable, year five, Gross charge-offs			0
Financing receivable, more than five years, Gross charge-offs			250
Revolving Loans Amortized Cost Basis			0		0
Revolving Loans Converted to Term			0		0
Total			250		0
Commercial real estate | Non-owner occupied | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	3,057		3,057		15,127
Financing receivable, year two	13,810		13,810		37,938
Financing receivable, year three	36,000		36,000		347,939
Financing receivable, year four	385,373		385,373		95,368
Financing receivable, more than four years					1,082,553
Financing receivable, year five	138,952		138,952
Financing receivable, more than five years	1,124,892		1,124,892
Revolving Loans Amortized Cost Basis	41,734		41,734		42,257
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	1,743,818		1,743,818		1,621,182
Commercial real estate | Non-owner occupied | Special mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					9,026
Financing receivable, year five	0		0
Financing receivable, more than five years	58,762		58,762
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	58,762		58,762		9,026
Commercial real estate | Non-owner occupied | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					27,389
Financing receivable, year five	0		0
Financing receivable, more than five years	61,460		61,460
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	61,460		61,460		27,389
Commercial real estate | Non-owner occupied | Doubtful
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	0		0		0
Commercial real estate | Owner occupied
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	19,286		19,286		10,840
Financing receivable, year two	11,012		11,012		23,340
Financing receivable, year three	27,972		27,972		62,849
Financing receivable, year four	123,099		123,099		47,056
Financing receivable, more than four years					212,658
Financing receivable, year five	88,465		88,465
Financing receivable, more than five years	433,157		433,157
Revolving Loans Amortized Cost Basis	6,248		6,248		3,357
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	709,239		709,239		360,100
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Financing receivable, year one, Gross charge-offs			0		0
Financing receivable, year two, Gross charge-offs			0		0
Financing receivable, year three, Gross charge-offs			0		0
Financing receivable, year four, Gross charge-offs			0		0
Financing receivable, Gross charge-offs more than four years					0
Financing receivable, year five, Gross charge-offs			0
Financing receivable, more than five years, Gross charge-offs			0
Revolving Loans Amortized Cost Basis			0		0
Revolving Loans Converted to Term			0		0
Total			0		0
Commercial real estate | Owner occupied | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	19,286		19,286		10,840
Financing receivable, year two	11,012		11,012		23,340
Financing receivable, year three	27,972		27,972		62,849
Financing receivable, year four	112,543		112,543		47,056
Financing receivable, more than four years					189,436
Financing receivable, year five	76,237		76,237
Financing receivable, more than five years	386,615		386,615
Revolving Loans Amortized Cost Basis	6,248		6,248		3,357
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	639,913		639,913		336,878
Commercial real estate | Owner occupied | Special mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	10,282		10,282		0
Financing receivable, more than four years					13,111
Financing receivable, year five	7,017		7,017
Financing receivable, more than five years	39,718		39,718
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	57,017		57,017		13,111
Commercial real estate | Owner occupied | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	274		274		0
Financing receivable, more than four years					10,111
Financing receivable, year five	5,211		5,211
Financing receivable, more than five years	6,824		6,824
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	12,309		12,309		10,111
Commercial real estate | Owner occupied | Doubtful
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	0		0		0
Commercial real estate | Construction and land development
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	236,608		236,608		34,891
Financing receivable, year two	179,266		179,266		13,515
Financing receivable, year three	73,857		73,857		34,985
Financing receivable, year four	23,823		23,823		141
Financing receivable, more than four years					20,796
Financing receivable, year five	5,049		5,049
Financing receivable, more than five years	16,573		16,573
Revolving Loans Amortized Cost Basis	600		600		102
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	535,776		535,776		104,430
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Financing receivable, year one, Gross charge-offs			0		0
Financing receivable, year two, Gross charge-offs			0		0
Financing receivable, year three, Gross charge-offs			0		0
Financing receivable, year four, Gross charge-offs			0		0
Financing receivable, Gross charge-offs more than four years					0
Financing receivable, year five, Gross charge-offs			0
Financing receivable, more than five years, Gross charge-offs			0
Revolving Loans Amortized Cost Basis			0		0
Revolving Loans Converted to Term			0		0
Total			0		0
Commercial real estate | Construction and land development | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	236,608		236,608		34,891
Financing receivable, year two	179,266		179,266		13,515
Financing receivable, year three	73,857		73,857		34,985
Financing receivable, year four	13,823		13,823		141
Financing receivable, more than four years					20,355
Financing receivable, year five	5,049		5,049
Financing receivable, more than five years	13,586		13,586
Revolving Loans Amortized Cost Basis	600		600		102
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	522,789		522,789		103,989
Commercial real estate | Construction and land development | Special mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	10,000		10,000		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	10,000		10,000		0
Commercial real estate | Construction and land development | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					441
Financing receivable, year five	0		0
Financing receivable, more than five years	2,987		2,987
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	2,987		2,987		441
Commercial real estate | Construction and land development | Doubtful
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Financing receivable, year one	0		0		0
Financing receivable, year two	0		0		0
Financing receivable, year three	0		0		0
Financing receivable, year four	0		0		0
Financing receivable, more than four years					0
Financing receivable, year five	0		0
Financing receivable, more than five years	0		0
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term	0		0		0
Total loan and lease receivables before allowance for credit losses	$ 0		$ 0		$ 0

X

- Definition

Financing Receivable, Excluding Accrued Interest, Originated, More than Four Years before Current Fiscal Year

+ References

No definition available.

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X

- Definition

Financing Receivable, Excluding Accrued Interest, Originated, More than Four Years before Current Fiscal Year, Writeoff

+ References

No definition available.

+ Details

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X

- Definition

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 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: 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

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- References

No definition available.

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X

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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