INVESTMENT SECURITIES - Schedule of Investment Securities' Gross Unrealized Losses and Fair Value by Investment Category (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	$ 1,530,406	$ 3,510,536
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	171,140	56,088
Available-for-sale debt securities, 12 months or longer, Fair Value	2,562,615	550,108
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	570,350	23,109
Available-for-sale debt securities, Total, Fair Value	4,093,021	4,060,644
Available-for-sale debt securities, Total, Unrealized Loss	741,490	79,197
CMO
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	158,449	411,347
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	13,855	12,730
Available-for-sale debt securities, 12 months or longer, Fair Value	347,931	35,638
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	88,599	1,903
Available-for-sale debt securities, Total, Fair Value	506,380	446,985
Available-for-sale debt securities, Total, Unrealized Loss	102,454	14,633
FNMA MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	1,237,560	3,018,606
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	145,752	41,021
Available-for-sale debt securities, 12 months or longer, Fair Value	2,012,698	356,665
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	427,026	12,772
Available-for-sale debt securities, Total, Fair Value	3,250,258	3,375,271
Available-for-sale debt securities, Total, Unrealized Loss	572,778	53,793
FHLMC MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	102,321	11,227
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	9,268	348
Available-for-sale debt securities, 12 months or longer, Fair Value	19,671	1,917
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	4,287	168
Available-for-sale debt securities, Total, Fair Value	121,992	13,144
Available-for-sale debt securities, Total, Unrealized Loss	13,555	516
GNMA MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	32,076	4,847
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	2,265	71
Available-for-sale debt securities, 12 months or longer, Fair Value	4,030	0
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	713	0
Available-for-sale debt securities, Total, Fair Value	36,106	4,847
Available-for-sale debt securities, Total, Unrealized Loss	2,978	71
GSE agency notes
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair Value	0	64,509
Available-for-sale debt securities, Less than 12 months, Unrealized Loss	0	1,918
Available-for-sale debt securities, 12 months or longer, Fair Value	178,285	155,888
Available-for-sale debt securities, 12 months or longer, Unrealized Loss	49,725	8,266
Available-for-sale debt securities, Total, Fair Value	178,285	220,397
Available-for-sale debt securities, Total, Unrealized Loss	$ 49,725	$ 10,184

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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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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