INVESTMENT SECURITIES - Schedule of Investment Securities' Gross Unrealized Losses and Fair Value by Investment Category (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	$ 492,920	$ 1,530,406
Available-for-sale debt securities, Less than 12 months, Unrealized loss	24,096	171,140
Available-for-sale debt securities, 12 months or longer, Fair value	3,593,037	2,562,615
Available-for-sale debt securities, 12 months or longer, Unrealized loss	647,648	570,350
Available-for-sale debt securities, Total, Fair value	4,085,957	4,093,021
Available-for-sale debt securities, Total, Unrealized loss	671,744	741,490
CMO
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	52,883	158,449
Available-for-sale debt securities, Less than 12 months, Unrealized loss	2,417	13,855
Available-for-sale debt securities, 12 months or longer, Fair value	453,253	347,931
Available-for-sale debt securities, 12 months or longer, Unrealized loss	90,095	88,599
Available-for-sale debt securities, Total, Fair value	506,136	506,380
Available-for-sale debt securities, Total, Unrealized loss	92,512	102,454
FNMA MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	356,825	1,237,560
Available-for-sale debt securities, Less than 12 months, Unrealized loss	17,485	145,752
Available-for-sale debt securities, 12 months or longer, Fair value	2,878,998	2,012,698
Available-for-sale debt securities, 12 months or longer, Unrealized loss	502,492	427,026
Available-for-sale debt securities, Total, Fair value	3,235,823	3,250,258
Available-for-sale debt securities, Total, Unrealized loss	519,977	572,778
FHLMC MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	53,125	102,321
Available-for-sale debt securities, Less than 12 months, Unrealized loss	2,697	9,268
Available-for-sale debt securities, 12 months or longer, Fair value	68,958	19,671
Available-for-sale debt securities, 12 months or longer, Unrealized loss	8,728	4,287
Available-for-sale debt securities, Total, Fair value	122,083	121,992
Available-for-sale debt securities, Total, Unrealized loss	11,425	13,555
GNMA MBS
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	30,087	32,076
Available-for-sale debt securities, Less than 12 months, Unrealized loss	1,497	2,265
Available-for-sale debt securities, 12 months or longer, Fair value	9,659	4,030
Available-for-sale debt securities, 12 months or longer, Unrealized loss	1,134	713
Available-for-sale debt securities, Total, Fair value	39,746	36,106
Available-for-sale debt securities, Total, Unrealized loss	2,631	2,978
GSE agency notes
Available-for-sale debt securities:
Available-for-sale debt securities, Less than 12 months, Fair value	0	0
Available-for-sale debt securities, Less than 12 months, Unrealized loss	0	0
Available-for-sale debt securities, 12 months or longer, Fair value	182,169	178,285
Available-for-sale debt securities, 12 months or longer, Unrealized loss	45,199	49,725
Available-for-sale debt securities, Total, Fair value	182,169	178,285
Available-for-sale debt securities, Total, Unrealized loss	$ 45,199	$ 49,725

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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