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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
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Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | $ 10,116,941 | $ 9,244,661
Loans held for investment, net of fees and costs | 10,116,941 | 9,244,661
Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 9,728,056 | 8,531,760
2022 | 2,198,248 |
2021 | 1,764,434 | 1,828,115
2020 | 1,264,780 | 1,473,478
2019 | 1,014,976 | 1,174,655
2018 | 546,117 | 606,030
2017 and Prior | 2,262,606 | 752,529
2016 and Prior |  | 2,114,513
Revolving | 647,221 | 552,538
Revolving-Term | 29,674 | 29,902
Loans held for investment, net of fees and costs | 9,728,056 | 8,531,760
Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 180,575 | 173,964
2022 | 7,230 |
2021 |  | 6,003
2020 | 942 | 15,891
2019 | 59,040 | 54,365
2018 | 27,747 | 21,926
2017 and Prior | 75,333 | 23,775
2016 and Prior |  | 45,900
Revolving | 9,049 | 4,071
Revolving-Term | 1,234 | 2,033
Loans held for investment, net of fees and costs | 180,575 | 173,964
Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 179,549 | 496,912
2022 | 4,916 |
2021 | 1,209 | 4,833
2020 | 24,542 | 11,011
2019 | 19,892 | 50,235
2018 | 32,419 | 97,994
2017 and Prior | 72,766 | 91,019
2016 and Prior |  | 196,506
Revolving | 12,635 | 30,823
Revolving-Term | 11,170 | 14,491
Loans held for investment, net of fees and costs | 179,549 | 496,912
Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 19,834 | 25,127
2021 | 412 | 550
2020 |  | 1,621
2019 | 8,332 | 10,074
2018 | 752 | 775
2017 and Prior | 10,338 | 11,107
Revolving |  | 1,000
Loans held for investment, net of fees and costs | 19,834 | 25,127
Total real estate loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 9,195,863 | 8,294,204
Loans held for investment, net of fees and costs | 9,195,863 | 8,294,204
Excludes Other Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 10,108,014 | 9,227,763
2022 | 2,210,394 |
2021 | 1,766,055 | 1,839,501
2020 | 1,290,264 | 1,502,001
2019 | 1,102,240 | 1,289,329
2018 | 607,035 | 726,725
2017 and Prior | 2,421,043 | 878,430
2016 and Prior |  | 2,356,919
Revolving | 668,905 | 588,432
Revolving-Term | 42,078 | 46,426
Loans held for investment, net of fees and costs | 10,108,014 | 9,227,763
One-to-four family residential and cooperative/condominium apartment |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 722,081 | 669,282
2022 | 155,591 |
2021 | 110,542 | 129,679
2020 | 76,795 | 89,096
2019 | 67,182 | 82,568
2018 | 68,124 | 76,726
2017 and Prior | 185,115 | 80,365
2016 and Prior |  | 145,946
Revolving | 45,152 | 50,724
Revolving-Term | 13,580 | 14,178
Loans held for investment, net of fees and costs | 722,081 | 669,282
One-to-four family residential and cooperative/condominium apartment | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 703,484 | 640,776
2022 | 155,591 |
2021 | 110,542 | 129,679
2020 | 75,764 | 86,028
2019 | 65,953 | 80,195
2018 | 66,976 | 75,354
2017 and Prior | 172,012 | 77,829
2016 and Prior |  | 129,276
Revolving | 44,573 | 49,878
Revolving-Term | 12,073 | 12,537
Loans held for investment, net of fees and costs | 703,484 | 640,776
One-to-four family residential and cooperative/condominium apartment | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 4,894 | 6,296
2020 |  | 1,124
2019 |  | 335
2018 | 739 | 752
2017 and Prior | 2,845 | 334
2016 and Prior |  | 2,158
Revolving | 579 | 846
Revolving-Term | 731 | 747
Loans held for investment, net of fees and costs | 4,894 | 6,296
One-to-four family residential and cooperative/condominium apartment | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 13,703 | 22,187
2020 | 1,031 | 1,944
2019 | 1,229 | 2,038
2018 | 409 | 597
2017 and Prior | 10,258 | 2,202
2016 and Prior |  | 14,512
Revolving-Term | 776 | 894
Loans held for investment, net of fees and costs | 13,703 | 22,187
One-to-four family residential and cooperative/condominium apartment | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans |  | 23
2018 |  | 23
Loans held for investment, net of fees and costs |  | 23
Multifamily residential and residential mixed-use |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 3,968,244 | 3,356,346
2022 | 1,208,492 |
2021 | 585,735 | 590,462
2020 | 338,510 | 353,747
2019 | 425,928 | 505,089
2018 | 158,935 | 183,616
2017 and Prior | 1,238,304 | 398,804
2016 and Prior |  | 1,309,248
Revolving | 12,340 | 14,555
Revolving-Term |  | 825
Loans held for investment, net of fees and costs | 3,968,244 | 3,356,346
Multifamily residential and residential mixed-use | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 3,790,781 | 3,029,631
2022 | 1,208,492 |
2021 | 585,735 | 590,462
2020 | 326,154 | 341,206
2019 | 393,385 | 455,277
2018 | 125,893 | 151,226
2017 and Prior | 1,138,782 | 332,749
2016 and Prior |  | 1,145,609
Revolving | 12,340 | 12,277
Revolving-Term |  | 825
Loans held for investment, net of fees and costs | 3,790,781 | 3,029,631
Multifamily residential and residential mixed-use | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 94,253 | 63,595
2020 |  | 11,040
2019 | 25,513 | 14,486
2018 | 12,646 |
2017 and Prior | 56,094 | 11,817
2016 and Prior |  | 26,252
Loans held for investment, net of fees and costs | 94,253 | 63,595
Multifamily residential and residential mixed-use | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 83,210 | 263,120
2020 | 12,356 | 1,501
2019 | 7,030 | 35,326
2018 | 20,396 | 32,390
2017 and Prior | 43,428 | 54,238
2016 and Prior |  | 137,387
Revolving |  | 2,278
Loans held for investment, net of fees and costs | 83,210 | 263,120
Commercial real estate ("CRE") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 4,264,519 | 3,945,948
2022 | 734,936 |
2021 | 874,936 | 882,483
2020 | 784,265 | 851,450
2019 | 536,450 | 575,675
2018 | 330,936 | 370,839
2017 and Prior | 944,121 | 341,690
2016 and Prior |  | 874,440
Revolving | 53,018 | 43,183
Revolving-Term | 5,857 | 6,188
Loans held for investment, net of fees and costs | 4,264,519 | 3,945,948
Commercial real estate ("CRE") | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 4,163,468 | 3,719,799
2022 | 732,046 |
2021 | 874,785 | 872,049
2020 | 780,530 | 848,694
2019 | 495,212 | 529,182
2018 | 307,616 | 306,360
2017 and Prior | 914,404 | 298,904
2016 and Prior |  | 815,239
Revolving | 53,018 | 43,183
Revolving-Term | 5,857 | 6,188
Loans held for investment, net of fees and costs | 4,163,468 | 3,719,799
Commercial real estate ("CRE") | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 64,336 | 93,792
2022 | 2,890 |
2021 |  | 6,003
2020 |  | 1,024
2019 | 33,240 | 39,305
2018 | 12,720 | 18,983
2017 and Prior | 15,486 | 11,039
2016 and Prior |  | 17,438
Loans held for investment, net of fees and costs | 64,336 | 93,792
Commercial real estate ("CRE") | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 36,715 | 132,251
2021 | 151 | 4,431
2020 | 3,735 | 1,732
2019 | 7,998 | 7,082
2018 | 10,600 | 45,496
2017 and Prior | 14,231 | 31,747
2016 and Prior |  | 41,763
Loans held for investment, net of fees and costs | 36,715 | 132,251
Commercial real estate ("CRE") | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans |  | 106
2019 |  | 106
Loans held for investment, net of fees and costs |  | 106
Acquisition, development, and construction |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 241,019 | 322,628
2022 | 25,431 |
2021 | 144,151 | 142,123
2020 | 18,088 | 77,427
2019 | 20,043 | 56,885
2018 | 6,349 | 36,956
2017 and Prior | 2,573 | 6,809
2016 and Prior |  | 774
Revolving | 24,097 | 1,066
Revolving-Term | 287 | 588
Loans held for investment, net of fees and costs | 241,019 | 322,628
Acquisition, development, and construction | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 240,362 | 307,960
2022 | 25,431 |
2021 | 143,494 | 142,123
2020 | 18,088 | 76,259
2019 | 20,043 | 56,885
2018 | 6,349 | 23,456
2017 and Prior | 2,573 | 6,809
2016 and Prior |  | 774
Revolving | 24,097 | 1,066
Revolving-Term | 287 | 588
Loans held for investment, net of fees and costs | 240,362 | 307,960
Acquisition, development, and construction | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans |  | 1,078
2020 |  | 1,078
Loans held for investment, net of fees and costs |  | 1,078
Acquisition, development, and construction | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 657 | 13,590
2021 | 657 |
2020 |  | 90
2018 |  | 13,500
Loans held for investment, net of fees and costs | 657 | 13,590
Commercial and Industrial ("C&I") Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 912,151 | 933,559
2022 | 85,944 |
2021 | 50,691 | 94,754
2020 | 72,606 | 130,281
2019 | 52,637 | 69,112
2018 | 42,691 | 58,588
2017 and Prior | 50,930 | 50,762
2016 and Prior |  | 26,511
Revolving | 534,298 | 478,904
Revolving-Term | 22,354 | 24,647
Loans held for investment, net of fees and costs | 912,151 | 933,559
Commercial and Industrial ("C&I") Loans | Pass |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 829,961 | 833,594
2022 | 76,688 |
2021 | 49,878 | 93,802
2020 | 64,244 | 121,291
2019 | 40,383 | 53,116
2018 | 39,283 | 49,634
2017 and Prior | 34,835 | 36,238
2016 and Prior |  | 23,615
Revolving | 513,193 | 446,134
Revolving-Term | 11,457 | 9,764
Loans held for investment, net of fees and costs | 829,961 | 833,594
Commercial and Industrial ("C&I") Loans | Special Mention |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 17,092 | 9,203
2022 | 4,340 |
2020 | 942 | 1,625
2019 | 287 | 239
2018 | 1,642 | 2,191
2017 and Prior | 908 | 585
2016 and Prior |  | 52
Revolving | 8,470 | 3,225
Revolving-Term | 503 | 1,286
Loans held for investment, net of fees and costs | 17,092 | 9,203
Commercial and Industrial ("C&I") Loans | Substandard |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 45,264 | 65,764
2022 | 4,916 |
2021 | 401 | 402
2020 | 7,420 | 5,744
2019 | 3,635 | 5,789
2018 | 1,014 | 6,011
2017 and Prior | 4,849 | 2,832
2016 and Prior |  | 2,844
Revolving | 12,635 | 28,545
Revolving-Term | 10,394 | 13,597
Loans held for investment, net of fees and costs | 45,264 | 65,764
Commercial and Industrial ("C&I") Loans | Doubtful |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 19,834 | 24,998
2021 | 412 | 550
2020 |  | 1,621
2019 | 8,332 | 9,968
2018 | 752 | 752
2017 and Prior | 10,338 | 11,107
Revolving |  | 1,000
Loans held for investment, net of fees and costs | 19,834 | 24,998
Other Loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 8,927 | 16,898
Loans held for investment, net of fees and costs | 8,927 | 16,898
Other Loans | Credit Risk Profile |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 8,927 |
Loans held for investment, net of fees and costs | 8,927 |
Other Loans | Performing |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans |  | 16,533
Loans held for investment, net of fees and costs |  | 16,533
Other Loans | Performing | Credit Risk Profile |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans | 8,927 |
Loans held for investment, net of fees and costs | $ 8,927 |
Other Loans | Non-Accrual |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Total Loans |  | 365
Loans held for investment, net of fees and costs |  | $ 365

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