INVESTMENT SECURITIES - Amortized Cost and Fair Value of AFS Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 2,283,912	$ 1,816,061
Gross Unrealized Gains	3,861	11,439
Gross Unrealized Losses	(46,939)	(43,949)
Fair Value	2,240,834	1,783,551
Traditional securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	2,076,480	1,616,058
Gross Unrealized Gains	3,861	7,940
Gross Unrealized Losses	(45,809)	(43,949)
Fair Value	2,034,532	1,580,049
GSE certificates & CMOs
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	725,173	580,446
Gross Unrealized Gains	2,457	5,258
Gross Unrealized Losses	(21,627)	(18,634)
Fair Value	706,003	567,070
Non-GSE certificates & CMOs
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	458,967	281,787
Gross Unrealized Gains	598	1,523
Gross Unrealized Losses	(11,408)	(10,078)
Fair Value	448,157	273,232
Asset-Backed Securities ("ABS")
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	793,598	638,635
Gross Unrealized Gains	731	1,005
Gross Unrealized Losses	(10,136)	(10,472)
Fair Value	784,193	629,168
Corporate
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	88,068	100,000
Gross Unrealized Gains	75	117
Gross Unrealized Losses	(2,198)	(4,613)
Fair Value	85,945	95,504
Other
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	10,674	15,190
Gross Unrealized Gains	0	37
Gross Unrealized Losses	(440)	(152)
Fair Value	10,234	15,075
Property Assessed Clean Energy ("PACE") assessments
Debt Securities, Available-for-Sale [Line Items]
Fair Value	206,302	203,502
Residential PACE assessments
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	207,432	200,003
Gross Unrealized Gains	0	3,499
Gross Unrealized Losses	(1,130)	0
Fair Value	$ 206,302	$ 203,502

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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