INVESTMENT SECURITIES - Schedule of Unrealized Losses on Available for Sale Securities and Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	$ 1,123,446	$ 355,920
Available for sale, less than 12 months, unrealized losses	8,405	1,609
Available for sale, 12 months or longer, fair value	370,558	437,542
Available for sale, 12 months or longer, unrealized losses	38,534	42,340
Available for sale, total fair value	1,494,004	793,462
Available for sale, total unrealized losses	46,939	43,949
GSE certificates & CMOs
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	326,432	57,671
Available for sale, less than 12 months, unrealized losses	3,774	342
Available for sale, 12 months or longer, fair value	118,343	138,879
Available for sale, 12 months or longer, unrealized losses	17,853	18,292
Available for sale, total fair value	444,775	196,550
Available for sale, total unrealized losses	21,627	18,634
Non-GSE certificates & CMOs
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	245,471	5,893
Available for sale, less than 12 months, unrealized losses	1,673	20
Available for sale, 12 months or longer, fair value	106,065	118,250
Available for sale, 12 months or longer, unrealized losses	9,735	10,058
Available for sale, total fair value	351,536	124,143
Available for sale, total unrealized losses	11,408	10,078
Asset-Backed Securities ("ABS")
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	315,123	284,508
Available for sale, less than 12 months, unrealized losses	1,202	1,095
Available for sale, 12 months or longer, fair value	85,164	105,027
Available for sale, 12 months or longer, unrealized losses	8,934	9,377
Available for sale, total fair value	400,287	389,535
Available for sale, total unrealized losses	10,136	10,472
Corporate
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	19,884	0
Available for sale, less than 12 months, unrealized losses	186	0
Available for sale, 12 months or longer, fair value	60,986	75,386
Available for sale, 12 months or longer, unrealized losses	2,012	4,613
Available for sale, total fair value	80,870	75,386
Available for sale, total unrealized losses	2,198	4,613
Other
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	10,234	7,848
Available for sale, less than 12 months, unrealized losses	440	152
Available for sale, 12 months or longer, fair value	0	0
Available for sale, 12 months or longer, unrealized losses	0	0
Available for sale, total fair value	10,234	7,848
Available for sale, total unrealized losses	440	$ 152
Residential PACE assessments
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Available for sale, less than 12 months, fair value	206,302
Available for sale, less than 12 months, unrealized losses	1,130
Available for sale, 12 months or longer, fair value	0
Available for sale, 12 months or longer, unrealized losses	0
Available for sale, total fair value	206,302
Available for sale, total unrealized losses	$ 1,130

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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