INVESTMENT SECURITIES - Amortized Cost and Fair Value of AFS Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,816,061	$ 1,696,237
Gross Unrealized Gains	11,439	5,491
Gross Unrealized Losses	(43,949)	(72,670)
Fair Value	1,783,551	1,629,058
Traditional securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,616,058	1,546,053
Gross Unrealized Gains	7,940	3,664
Gross Unrealized Losses	(43,949)	(72,670)
Fair Value	1,580,049	1,477,047
Government sponsored entities ("GSE") certificates & Collateralized mortgage obligations ("CMOs")
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	580,446	537,313
Gross Unrealized Gains	5,258	2,072
Gross Unrealized Losses	(18,634)	(31,227)
Fair Value	567,070	508,158
Non-GSE certificates & CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	281,787	229,513
Gross Unrealized Gains	1,523	243
Gross Unrealized Losses	(10,078)	(15,581)
Fair Value	273,232	214,175
ABS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	638,635	665,548
Gross Unrealized Gains	1,005	1,349
Gross Unrealized Losses	(10,472)	(14,563)
Fair Value	629,168	652,334
Corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	100,000	109,482
Gross Unrealized Gains	117	0
Gross Unrealized Losses	(4,613)	(11,167)
Fair Value	95,504	98,315
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,190	4,197
Gross Unrealized Gains	37	0
Gross Unrealized Losses	(152)	(132)
Fair Value	15,075	4,065
Property Assessed Clean Energy ("PACE") assessments
Debt Securities, Available-for-sale [Line Items]
Fair Value	203,502	152,011
Residential PACE assessments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	200,003	150,184
Gross Unrealized Gains	3,499	1,827
Gross Unrealized Losses	0	0
Fair Value	$ 203,502	$ 152,011

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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