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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | $ 10,566,831 | $ 9,244,661
Principal balances outstanding | 10,566,831 | 9,244,661
Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 2,845,426 |
2021 | 1,733,872 | 1,828,115
2020 | 1,196,053 | 1,473,478
2019 | 1,024,753 | 1,174,655
2018 | 522,005 | 606,030
2017 and Prior | 2,175,148 | 752,529
2016 and Prior |  | 2,114,513
Revolving | 726,711 | 552,538
Revolving-Term | 59,850 | 29,902
Total Loans | 10,283,818 | 8,531,760
Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 6,634 |
2021 |  | 6,003
2020 | 20,549 | 15,891
2019 | 17,365 | 54,365
2018 | 16,628 | 21,926
2017 and Prior | 31,664 | 23,775
2016 and Prior |  | 45,900
Revolving | 9,641 | 4,071
Revolving-Term | 1,204 | 2,033
Total Loans | 103,685 | 173,964
Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 5,242 |
2021 | 2,052 | 4,833
2020 | 23,234 | 11,011
2019 | 19,143 | 50,235
2018 | 22,819 | 97,994
2017 and Prior | 66,232 | 91,019
2016 and Prior |  | 196,506
Revolving | 11,290 | 30,823
Revolving-Term | 10,505 | 14,491
Total Loans | 160,517 | 496,912
Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 |  | 550
2020 |  | 1,621
2019 | 8,332 | 10,074
2018 | 752 | 775
2017 and Prior | 2,048 | 11,107
Revolving |  | 1,000
Total Loans | 11,132 | 25,127
Total real estate loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 9,487,440 | 8,294,204
Excludes Other Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 2,857,302 |
2021 | 1,735,924 | 1,839,501
2020 | 1,239,836 | 1,502,001
2019 | 1,069,593 | 1,289,329
2018 | 562,204 | 726,725
2017 and Prior | 2,275,092 | 878,430
2016 and Prior |  | 2,356,919
Revolving | 747,642 | 588,432
Revolving-Term | 71,559 | 46,426
Total Loans | 10,559,152 | 9,227,763
One-to-four family residential and cooperative/condominium apartment |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 225,031 |
2021 | 108,185 | 129,679
2020 | 73,758 | 89,096
2019 | 66,742 | 82,568
2018 | 67,180 | 76,726
2017 and Prior | 176,292 | 80,365
2016 and Prior |  | 145,946
Revolving | 41,751 | 50,724
Revolving-Term | 14,382 | 14,178
Total Loans | 773,321 | 669,282
One-to-four family residential and cooperative/condominium apartment | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 225,031 |
2021 | 108,185 | 129,679
2020 | 72,732 | 86,028
2019 | 65,515 | 80,195
2018 | 66,038 | 75,354
2017 and Prior | 164,338 | 77,829
2016 and Prior |  | 129,276
Revolving | 41,172 | 49,878
Revolving-Term | 12,563 | 12,537
Total Loans | 755,574 | 640,776
One-to-four family residential and cooperative/condominium apartment | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 |  | 1,124
2019 |  | 335
2018 | 735 | 752
2017 and Prior | 1,175 | 334
2016 and Prior |  | 2,158
Revolving | 579 | 846
Revolving-Term | 726 | 747
Total Loans | 3,215 | 6,296
One-to-four family residential and cooperative/condominium apartment | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 1,026 | 1,944
2019 | 1,227 | 2,038
2018 | 407 | 597
2017 and Prior | 10,779 | 2,202
2016 and Prior |  | 14,512
Revolving-Term | 1,093 | 894
Total Loans | 14,532 | 22,187
One-to-four family residential and cooperative/condominium apartment | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2018 |  | 23
Total Loans |  | 23
Multifamily residential and residential mixed-use |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 1,386,549 |
2021 | 582,393 | 590,462
2020 | 328,718 | 353,747
2019 | 414,117 | 505,089
2018 | 147,385 | 183,616
2017 and Prior | 1,155,080 | 398,804
2016 and Prior |  | 1,309,248
Revolving | 12,584 | 14,555
Revolving-Term |  | 825
Total Loans | 4,026,826 | 3,356,346
Multifamily residential and residential mixed-use | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 1,386,549 |
2021 | 582,393 | 590,462
2020 | 316,424 | 341,206
2019 | 395,933 | 455,277
2018 | 127,074 | 151,226
2017 and Prior | 1,107,281 | 332,749
2016 and Prior |  | 1,145,609
Revolving | 12,584 | 12,277
Revolving-Term |  | 825
Total Loans | 3,928,238 | 3,029,631
Multifamily residential and residential mixed-use | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 |  | 11,040
2019 | 11,183 | 14,486
2017 and Prior | 14,168 | 11,817
2016 and Prior |  | 26,252
Total Loans | 25,351 | 63,595
Multifamily residential and residential mixed-use | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 12,294 | 1,501
2019 | 7,001 | 35,326
2018 | 20,311 | 32,390
2017 and Prior | 33,631 | 54,238
2016 and Prior |  | 137,387
Revolving |  | 2,278
Total Loans | 73,237 | 263,120
Commercial real estate ("CRE") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 1,024,486 |
2021 | 854,391 | 882,483
2020 | 777,757 | 851,450
2019 | 522,932 | 575,675
2018 | 323,768 | 370,839
2017 and Prior | 895,167 | 341,690
2016 and Prior |  | 874,440
Revolving | 34,362 | 43,183
Revolving-Term | 24,767 | 6,188
Total Loans | 4,457,630 | 3,945,948
Commercial real estate ("CRE") | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 1,021,622 |
2021 | 854,240 | 872,049
2020 | 753,552 | 848,694
2019 | 510,332 | 529,182
2018 | 308,265 | 306,360
2017 and Prior | 868,099 | 298,904
2016 and Prior |  | 815,239
Revolving | 34,362 | 43,183
Revolving-Term | 24,767 | 6,188
Total Loans | 4,375,239 | 3,719,799
Commercial real estate ("CRE") | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 2,864 |
2021 |  | 6,003
2020 | 19,655 | 1,024
2019 | 4,653 | 39,305
2018 | 14,372 | 18,983
2017 and Prior | 15,478 | 11,039
2016 and Prior |  | 17,438
Total Loans | 57,022 | 93,792
Commercial real estate ("CRE") | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 151 | 4,431
2020 | 4,550 | 1,732
2019 | 7,947 | 7,082
2018 | 1,131 | 45,496
2017 and Prior | 11,590 | 31,747
2016 and Prior |  | 41,763
Total Loans | 25,369 | 132,251
Commercial real estate ("CRE") | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 |  | 106
Total Loans |  | 106
Acquisition, development, and construction |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 36,877 |
2021 | 153,200 | 142,123
2020 | 11,242 | 77,427
2019 | 15,943 | 56,885
2018 |  | 36,956
2017 and Prior | 2,087 | 6,809
2016 and Prior |  | 774
Revolving | 10,033 | 1,066
Revolving-Term | 281 | 588
Total Loans | 229,663 | 322,628
Acquisition, development, and construction | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 36,877 |
2021 | 152,543 | 142,123
2020 | 11,242 | 76,259
2019 | 15,943 | 56,885
2018 |  | 23,456
2017 and Prior | 2,087 | 6,809
2016 and Prior |  | 774
Revolving | 10,033 | 1,066
Revolving-Term | 281 | 588
Total Loans | 229,006 | 307,960
Acquisition, development, and construction | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 |  | 1,078
Total Loans |  | 1,078
Acquisition, development, and construction | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 657 |
2020 |  | 90
2018 |  | 13,500
Total Loans | 657 | 13,590
Commercial and Industrial ("C&I") Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 184,359 |
2021 | 37,755 | 94,754
2020 | 48,361 | 130,281
2019 | 49,859 | 69,112
2018 | 23,871 | 58,588
2017 and Prior | 46,466 | 50,762
2016 and Prior |  | 26,511
Revolving | 648,912 | 478,904
Revolving-Term | 32,129 | 24,647
Total Loans | 1,071,712 | 933,559
Commercial and Industrial ("C&I") Loans | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 175,347 |
2021 | 36,511 | 93,802
2020 | 42,103 | 121,291
2019 | 37,030 | 53,116
2018 | 20,628 | 49,634
2017 and Prior | 33,343 | 36,238
2016 and Prior |  | 23,615
Revolving | 628,560 | 446,134
Revolving-Term | 22,239 | 9,764
Total Loans | 995,761 | 833,594
Commercial and Industrial ("C&I") Loans | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 3,770 |
2020 | 894 | 1,625
2019 | 1,529 | 239
2018 | 1,521 | 2,191
2017 and Prior | 843 | 585
2016 and Prior |  | 52
Revolving | 9,062 | 3,225
Revolving-Term | 478 | 1,286
Total Loans | 18,097 | 9,203
Commercial and Industrial ("C&I") Loans | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2022 | 5,242 |
2021 | 1,244 | 402
2020 | 5,364 | 5,744
2019 | 2,968 | 5,789
2018 | 970 | 6,011
2017 and Prior | 10,232 | 2,832
2016 and Prior |  | 2,844
Revolving | 11,290 | 28,545
Revolving-Term | 9,412 | 13,597
Total Loans | 46,722 | 65,764
Commercial and Industrial ("C&I") Loans | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 |  | 550
2020 |  | 1,621
2019 | 8,332 | 9,968
2018 | 752 | 752
2017 and Prior | 2,048 | 11,107
Revolving |  | 1,000
Total Loans | 11,132 | 24,998
Other Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 7,679 | 16,898
Other Loans | Credit Risk Profile |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Principal balances outstanding | 7,679 | 16,898
Other Loans | Performing | Credit Risk Profile |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Principal balances outstanding | 7,580 | 16,533
Other Loans | Non-Accrual | Credit Risk Profile |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Principal balances outstanding | $ 99 | $ 365

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