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PORTFOLIO LOANS - Schedule of Risk Grades Segregated by Category and Class of Portfolio Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	$ 13,598,266	$ 7,697,087
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	11,824,501	6,764,070
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	1,291,575	756,610
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	332,765	92,296
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	103,329	62,023
Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	46,096	22,088
Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	10,919,490	5,552,288
Commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	9,172,355	4,635,264
Commercial loans | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	1,284,255	747,202
Commercial loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	325,157	91,414
Commercial loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	100,564	59,480
Commercial loans | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	37,159	18,928
Commercial loans | C&I and other commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	4,395,871	1,904,515
Commercial loans | C&I and other commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	3,707,153	1,545,338
Commercial loans | C&I and other commercial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	433,278	281,424
Commercial loans | C&I and other commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	152,267	36,152
Commercial loans | C&I and other commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	74,109	37,749
Commercial loans | C&I and other commercial | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	29,064	3,852
Commercial loans | CRE
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	5,424,095	3,269,564
Commercial loans | CRE | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	4,453,517	2,744,018
Commercial loans | CRE | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	794,313	438,945
Commercial loans | CRE | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	147,237	55,041
Commercial loans | CRE | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	21,228	16,507
Commercial loans | CRE | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	7,800	15,053
Commercial loans | Real estate construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	1,099,524	378,209
Commercial loans | Real estate construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	1,011,685	345,908
Commercial loans | Real estate construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	56,664	26,833
Commercial loans | Real estate construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	25,653	221
Commercial loans | Real estate construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	5,227	5,224
Commercial loans | Real estate construction | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	295	23
Retail loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,678,776	2,144,799
Retail loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,652,146	2,128,806
Retail loans | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	7,320	9,408
Retail loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	7,608	882
Retail loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,765	2,543
Retail loans | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	8,937	3,160
Retail loans | CRE
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,196,246	1,696,457
Retail loans | CRE | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,170,254	1,680,640
Retail loans | CRE | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	7,320	9,408
Retail loans | CRE | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	7,608	882
Retail loans | CRE | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	2,759	2,543
Retail loans | CRE | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	8,305	2,984
Retail loans | Retail other
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	482,530	448,342
Retail loans | Retail other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	481,892	448,166
Retail loans | Retail other | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	0	0
Retail loans | Retail other | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	0	0
Retail loans | Retail other | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	6	0
Retail loans | Retail other | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total portfolio loans	$ 632	$ 176

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

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