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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total | $ 10,763,265 |  | $ 10,766,837
Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 131,925 |  | 922,902
2023/2022 | 919,428 |  | 2,700,103
2022/2021 | 2,712,977 |  | 1,582,274
2021/2020 | 1,564,118 |  | 954,855
2020/2019 | 954,980 |  | 960,030
2019/2018 and Prior | 3,129,516 |  | 2,257,567
Revolving | 706,798 |  | 704,128
Revolving-Term | 75,148 |  | 60,048
Total | 10,194,890 |  | 10,141,907
Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 |  |  | 481
2023/2022 | 456 |  | 53,182
2022/2021 | 16,844 |  | 45,366
2021/2020 | 45,237 |  | 92,825
2020/2019 | 91,319 |  | 27,827
2019/2018 and Prior | 80,866 |  | 70,219
Revolving | 20,788 |  | 21,267
Revolving-Term | 8,098 |  | 26,082
Total | 263,608 |  | 337,249
Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 |  |  | 1,857
2022/2021 | 9,025 |  | 2,196
2021/2020 | 2,802 |  | 96,805
2020/2019 | 85,699 |  | 14,483
2019/2018 and Prior | 164,323 |  | 130,103
Revolving | 16,492 |  | 15,567
Revolving-Term | 20,508 |  | 20,167
Total | 298,849 |  | 281,178
Doubtful |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 and Prior | 748 |  | 748
Total | 748 |  | 748
Business loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 69,153 |  | 259,180
2023/2022 | 255,930 |  | 434,299
2022/2021 | 417,317 |  | 200,169
2021/2020 | 197,240 |  | 165,092
2020/2019 | 161,212 |  | 160,799
2019/2018 and Prior | 479,503 |  | 339,404
Revolving | 669,079 |  | 670,394
Revolving-Term | 77,528 |  | 78,834
Total | 2,326,962 |  | 2,308,171
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2022/2021 | 80 |  | 77
YTD Gross Charge-Offs 2021/2020 |  |  | 38
YTD Gross Charge-Offs 2020/2019 |  |  | 4,166
YTD Gross Charge-Offs 2019/2018 and Prior |  |  | 2,229
YTD Gross Charge-Offs Revolving | 633 |  | 5,464
YTD Gross Charge-Offs Revolving-Term | 83 |  | 3,390
YTD Gross Charge-Offs | 796 | $ 2,029 | 15,364
Business loans | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 69,153 |  | 258,699
2023/2022 | 255,474 |  | 390,760
2022/2021 | 392,650 |  | 196,790
2021/2020 | 193,191 |  | 144,796
2020/2019 | 153,026 |  | 150,871
2019/2018 and Prior | 435,108 |  | 305,258
Revolving | 631,958 |  | 633,719
Revolving-Term | 51,322 |  | 35,079
Total | 2,181,882 |  | 2,115,972
Business loans | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 |  |  | 481
2023/2022 | 456 |  | 41,682
2022/2021 | 15,642 |  | 1,199
2021/2020 | 1,262 |  | 13,567
2020/2019 | 1,746 |  | 7,125
2019/2018 and Prior | 10,551 |  | 3,150
Revolving | 20,629 |  | 21,108
Revolving-Term | 7,401 |  | 25,306
Total | 57,687 |  | 113,618
Business loans | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 |  |  | 1,857
2022/2021 | 9,025 |  | 2,180
2021/2020 | 2,787 |  | 6,729
2020/2019 | 6,440 |  | 2,803
2019/2018 and Prior | 33,096 |  | 30,248
Revolving | 16,492 |  | 15,567
Revolving-Term | 18,805 |  | 18,449
Total | 86,645 |  | 77,833
Business loans | Doubtful |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 and Prior | 748 |  | 748
Total | 748 |  | 748
One-to-four family residential and cooperative/condominium apartment |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 7,113 |  | 170,601
2023/2022 | 167,096 |  | 213,479
2022/2021 | 210,948 |  | 102,684
2021/2020 | 101,157 |  | 70,529
2020/2019 | 67,202 |  | 62,693
2019/2018 and Prior | 275,342 |  | 221,875
Revolving | 31,290 |  | 31,364
Revolving-Term | 13,187 |  | 14,330
Total | 873,335 |  | 887,555
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs Revolving-Term |  |  | 14
YTD Gross Charge-Offs |  |  | 14
One-to-four family residential and cooperative/condominium apartment | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 7,113 |  | 170,601
2023/2022 | 167,096 |  | 213,479
2022/2021 | 210,948 |  | 102,684
2021/2020 | 101,157 |  | 69,524
2020/2019 | 66,202 |  | 62,356
2019/2018 and Prior | 266,235 |  | 213,131
Revolving | 31,131 |  | 31,205
Revolving-Term | 11,444 |  | 12,493
Total | 861,326 |  | 875,473
One-to-four family residential and cooperative/condominium apartment | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 and Prior | 33 |  | 33
Revolving | 159 |  | 159
Revolving-Term | 697 |  | 776
Total | 889 |  | 968
One-to-four family residential and cooperative/condominium apartment | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2021/2020 |  |  | 1,005
2020/2019 | 1,000 |  | 337
2019/2018 and Prior | 9,074 |  | 8,711
Revolving-Term | 1,046 |  | 1,061
Total | 11,120 |  | 11,114
Multifamily residential and residential mixed-use |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 11,137 |  | 256,822
2023/2022 | 256,226 |  | 1,340,197
2022/2021 | 1,341,393 |  | 587,686
2021/2020 | 578,481 |  | 316,312
2020/2019 | 324,466 |  | 393,912
2019/2018 and Prior | 1,474,984 |  | 1,113,081
Revolving | 5,550 |  | 4,841
Revolving-Term | 4,311 |  | 4,325
Total | 3,996,548 |  | 4,017,176
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2019/2018 and Prior |  |  | 2
YTD Gross Charge-Offs |  |  | 2
Multifamily residential and residential mixed-use | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 11,137 |  | 256,822
2023/2022 | 256,226 |  | 1,340,197
2022/2021 | 1,340,191 |  | 578,352
2021/2020 | 569,200 |  | 283,633
2020/2019 | 291,859 |  | 384,937
2019/2018 and Prior | 1,339,820 |  | 981,820
Revolving | 5,550 |  | 4,841
Revolving-Term | 4,311 |  | 4,325
Total | 3,818,294 |  | 3,834,927
Multifamily residential and residential mixed-use | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 | 1,202 |  | 9,334
2021/2020 | 9,281 |  | 3,880
2020/2019 | 14,403 |  | 3,886
2019/2018 and Prior | 56,732 |  | 64,273
Total | 81,618 |  | 81,373
Multifamily residential and residential mixed-use | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2021/2020 |  |  | 28,799
2020/2019 | 18,204 |  | 5,089
2019/2018 and Prior | 78,432 |  | 66,988
Total | 96,636 |  | 100,876
Non-owner-occupied commercial real estate |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 40,593 |  | 220,045
2023/2022 | 217,651 |  | 738,133
2022/2021 | 737,938 |  | 665,134
2021/2020 | 661,106 |  | 582,652
2020/2019 | 579,118 |  | 370,018
2019/2018 and Prior | 1,130,405 |  | 783,840
Revolving | 11,223 |  | 11,919
Revolving-Term | 7,864 |  | 7,926
Total | 3,385,898 |  | 3,379,667
Non-owner-occupied commercial real estate | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 40,593 |  | 220,045
2023/2022 | 217,651 |  | 738,133
2022/2021 | 737,938 |  | 645,246
2021/2020 | 641,361 |  | 447,002
2020/2019 | 443,893 |  | 359,201
2019/2018 and Prior | 1,085,387 |  | 756,921
Revolving | 11,223 |  | 11,919
Revolving-Term | 7,864 |  | 7,926
Total | 3,185,910 |  | 3,186,393
Non-owner-occupied commercial real estate | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 |  |  | 19,872
2021/2020 | 19,730 |  | 75,378
2020/2019 | 75,170 |  | 4,563
2019/2018 and Prior | 13,550 |  | 2,763
Total | 108,450 |  | 102,576
Non-owner-occupied commercial real estate | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 |  |  | 16
2021/2020 | 15 |  | 60,272
2020/2019 | 60,055 |  | 6,254
2019/2018 and Prior | 31,468 |  | 24,156
Total | 91,538 |  | 90,698
Non-owner-occupied commercial real estate | Total real estate loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total | 3,385,898 |  | 3,379,667
Acquisition, development, and construction ("ADC") |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 3,929 |  | 16,735
2023/2022 | 22,981 |  | 29,034
2022/2021 | 31,250 |  | 74,163
2021/2020 | 74,173 |  | 9,900
2020/2019 |  |  | 14,918
2019/2018 and Prior | 15,219 |  | 437
Revolving | 26,936 |  | 22,444
Revolving-Term | 864 |  | 882
Total | 175,352 |  | 168,513
Acquisition, development, and construction ("ADC") | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 3,929 |  | 16,735
2023/2022 | 22,981 |  | 17,534
2022/2021 | 31,250 |  | 59,202
2021/2020 | 59,209 |  | 9,900
2020/2019 |  |  | 2,665
2019/2018 and Prior | 2,966 |  | 437
Revolving | 26,936 |  | 22,444
Revolving-Term | 207 |  | 225
Total | 147,478 |  | 129,142
Acquisition, development, and construction ("ADC") | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 |  |  | 11,500
2022/2021 |  |  | 14,961
2021/2020 | 14,964 |  |
2020/2019 |  |  | 12,253
Total | 14,964 |  | 38,714
Acquisition, development, and construction ("ADC") | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 and Prior | 12,253 |  |
Revolving-Term | 657 |  | 657
Total | 12,910 |  | 657
Other Loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total | 5,170 |  | 5,755
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs | 30 | $ 1 |
Other Loans | Credit Risk Profile |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total | 5,170 |  | 5,755
Other Loans | Performing | Credit Risk Profile |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total | 5,170 |  | 5,755
Excludes Other Loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2024/2023 | 131,925 |  | 923,383
2023/2022 | 919,884 |  | 2,755,142
2022/2021 | 2,738,846 |  | 1,629,836
2021/2020 | 1,612,157 |  | 1,144,485
2020/2019 | 1,131,998 |  | 1,002,340
2019/2018 and Prior | 3,375,453 |  | 2,458,637
Revolving | 744,078 |  | 740,962
Revolving-Term | 103,754 |  | 106,297
Total | 10,758,095 |  | 10,761,082
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2022/2021 | 80 |  | 77
YTD Gross Charge-Offs 2021/2020 |  |  | 38
YTD Gross Charge-Offs 2020/2019 |  |  | 4,166
YTD Gross Charge-Offs 2019/2018 and Prior |  |  | 2,231
YTD Gross Charge-Offs Revolving | 633 |  | 5,464
YTD Gross Charge-Offs Revolving-Term | 83 |  | 3,404
YTD Gross Charge-Offs | $ 796 |  | $ 15,380

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