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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments | $ 10,773,428 | $ 10,566,831 |
Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 922,902 |  |
2022/2021 | 2,700,103 | 2,845,426 |
2021/2020 | 1,582,274 | 1,733,872 |
2020/2019 | 954,855 | 1,196,053 |
2019/2018 | 960,030 | 1,024,753 |
2018/2017 and Prior | 2,257,567 | 522,005 |
2016 and Prior |  | 2,175,148 |
Revolving | 704,128 | 726,711 |
Revolving-Term | 60,048 | 59,850 |
Total loans, net of fair value hedge basis point adjustments | 10,141,907 | 10,283,818 |
Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 481 |  |
2022/2021 | 53,182 | 6,634 |
2021/2020 | 45,366 |  |
2020/2019 | 92,825 | 20,549 |
2019/2018 | 27,827 | 17,365 |
2018/2017 and Prior | 70,219 | 16,628 |
2016 and Prior |  | 31,664 |
Revolving | 21,267 | 9,641 |
Revolving-Term | 26,082 | 1,204 |
Total loans, net of fair value hedge basis point adjustments | 337,249 | 103,685 |
Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 | 1,857 | 5,242 |
2021/2020 | 2,196 | 2,052 |
2020/2019 | 96,805 | 23,234 |
2019/2018 | 14,483 | 19,143 |
2018/2017 and Prior | 130,103 | 22,819 |
2016 and Prior |  | 66,232 |
Revolving | 15,567 | 11,290 |
Revolving-Term | 20,167 | 10,505 |
Total loans, net of fair value hedge basis point adjustments | 281,178 | 160,517 |
Doubtful |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 |  | 8,332 |
2018/2017 and Prior | 748 | 752 |
2016 and Prior |  | 2,048 |
Total loans, net of fair value hedge basis point adjustments | 748 | 11,132 |
Total real estate loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments | 9,694,144 | 9,487,440 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2022/2021 |  | 477 |
YTD Gross Charge-Offs 2021/2020 |  | 4,720 |
YTD Gross Charge-Offs 2020/2019 |  | 2,088 |
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior |  | 2,414 |
YTD Gross Charge-Offs Revolving |  | 1,460 |
YTD Gross Charge-Offs Revolving-Term |  | 242 |
YTD Gross Charge-Offs | 16 | 11,401 | $ 3,817
Excludes Other Loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 |  | 2,857,302 |
2021/2020 |  | 1,735,924 |
2020/2019 |  | 1,239,836 |
2019/2018 |  | 1,069,593 |
2018/2017 and Prior |  | 562,204 |
2016 and Prior |  | 2,275,092 |
Revolving |  | 747,642 |
Revolving-Term |  | 71,559 |
Total loans, net of fair value hedge basis point adjustments |  | 10,559,152 |
C&I |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 61,252 |  |
2022/2021 | 152,914 | 184,359 |
2021/2020 | 28,109 | 37,755 |
2020/2019 | 31,853 | 48,361 |
2019/2018 | 28,114 | 49,859 |
2018/2017 and Prior | 49,862 | 23,871 |
2016 and Prior |  | 46,466 |
Revolving | 657,474 | 648,912 |
Revolving-Term | 57,360 | 32,129 |
Total loans, net of fair value hedge basis point adjustments | 1,066,938 | 1,071,712 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2022/2021 |  | 477 |
YTD Gross Charge-Offs 2021/2020 | 77 | 4,720 |
YTD Gross Charge-Offs 2020/2019 | 38 | 2,088 |
YTD Gross Charge-Offs 2019/2018 | 4,166 |  |
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior | 2,229 | 2,414 |
YTD Gross Charge-Offs Revolving | 5,464 | 1,460 |
YTD Gross Charge-Offs Revolving-Term | 3,390 | 242 |
YTD Gross Charge-Offs | 15,364 | 11,401 | 4,984
C&I | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 60,771 |  |
2022/2021 | 138,145 | 175,347 |
2021/2020 | 24,865 | 36,511 |
2020/2019 | 25,371 | 42,103 |
2019/2018 | 25,142 | 37,030 |
2018/2017 and Prior | 37,019 | 20,628 |
2016 and Prior |  | 33,343 |
Revolving | 620,799 | 628,560 |
Revolving-Term | 31,467 | 22,239 |
Total loans, net of fair value hedge basis point adjustments | 963,579 | 995,761 |
C&I | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 481 |  |
2022/2021 | 12,912 | 3,770 |
2021/2020 | 1,199 |  |
2020/2019 | 905 | 894 |
2019/2018 | 1,204 | 1,529 |
2018/2017 and Prior | 159 | 1,521 |
2016 and Prior |  | 843 |
Revolving | 21,108 | 9,062 |
Revolving-Term | 7,444 | 478 |
Total loans, net of fair value hedge basis point adjustments | 45,412 | 18,097 |
C&I | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 | 1,857 | 5,242 |
2021/2020 | 2,045 | 1,244 |
2020/2019 | 5,577 | 5,364 |
2019/2018 | 1,768 | 2,968 |
2018/2017 and Prior | 11,936 | 970 |
2016 and Prior |  | 10,232 |
Revolving | 15,567 | 11,290 |
Revolving-Term | 18,449 | 9,412 |
Total loans, net of fair value hedge basis point adjustments | 57,199 | 46,722 |
C&I | Doubtful |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2019/2018 |  | 8,332 |
2018/2017 and Prior | 748 | 752 |
2016 and Prior |  | 2,048 |
Total loans, net of fair value hedge basis point adjustments | 748 | 11,132 |
One-to-four family residential and cooperative/condominium apartment |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 170,601 |  |
2022/2021 | 213,479 | 225,031 |
2021/2020 | 102,684 | 108,185 |
2020/2019 | 70,529 | 73,758 |
2019/2018 | 62,693 | 66,742 |
2018/2017 and Prior | 221,875 | 67,180 |
2016 and Prior |  | 176,292 |
Revolving | 31,364 | 41,751 |
Revolving-Term | 14,330 | 14,382 |
Total loans, net of fair value hedge basis point adjustments | 887,555 | 773,321 |
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 |  | 20
One-to-four family residential and cooperative/condominium apartment | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 170,601 |  |
2022/2021 | 213,479 | 225,031 |
2021/2020 | 102,684 | 108,185 |
2020/2019 | 69,524 | 72,732 |
2019/2018 | 62,356 | 65,515 |
2018/2017 and Prior | 213,131 | 66,038 |
2016 and Prior |  | 164,338 |
Revolving | 31,205 | 41,172 |
Revolving-Term | 12,493 | 12,563 |
Total loans, net of fair value hedge basis point adjustments | 875,473 | 755,574 |
One-to-four family residential and cooperative/condominium apartment | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2018/2017 and Prior | 33 | 735 |
2016 and Prior |  | 1,175 |
Revolving | 159 | 579 |
Revolving-Term | 776 | 726 |
Total loans, net of fair value hedge basis point adjustments | 968 | 3,215 |
One-to-four family residential and cooperative/condominium apartment | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2020/2019 | 1,005 | 1,026 |
2019/2018 | 337 | 1,227 |
2018/2017 and Prior | 8,711 | 407 |
2016 and Prior |  | 10,779 |
Revolving-Term | 1,061 | 1,093 |
Total loans, net of fair value hedge basis point adjustments | 11,114 | 14,532 |
Multifamily residential and residential mixed-use |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 256,822 |  |
2022/2021 | 1,340,197 | 1,386,549 |
2021/2020 | 587,686 | 582,393 |
2020/2019 | 316,312 | 328,718 |
2019/2018 | 393,912 | 414,117 |
2018/2017 and Prior | 1,113,081 | 147,385 |
2016 and Prior |  | 1,155,080 |
Revolving | 4,841 | 12,584 |
Revolving-Term | 4,325 |  |
Total loans, net of fair value hedge basis point adjustments | 4,017,176 | 4,026,826 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior | 2 |  |
YTD Gross Charge-Offs | 2 |  | 391
Multifamily residential and residential mixed-use | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 256,822 |  |
2022/2021 | 1,340,197 | 1,386,549 |
2021/2020 | 578,352 | 582,393 |
2020/2019 | 283,633 | 316,424 |
2019/2018 | 384,937 | 395,933 |
2018/2017 and Prior | 981,820 | 127,074 |
2016 and Prior |  | 1,107,281 |
Revolving | 4,841 | 12,584 |
Revolving-Term | 4,325 |  |
Total loans, net of fair value hedge basis point adjustments | 3,834,927 | 3,928,238 |
Multifamily residential and residential mixed-use | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2021/2020 | 9,334 |  |
2020/2019 | 3,880 |  |
2019/2018 | 3,886 | 11,183 |
2018/2017 and Prior | 64,273 |  |
2016 and Prior |  | 14,168 |
Total loans, net of fair value hedge basis point adjustments | 81,373 | 25,351 |
Multifamily residential and residential mixed-use | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2020/2019 | 28,799 | 12,294 |
2019/2018 | 5,089 | 7,001 |
2018/2017 and Prior | 66,988 | 20,311 |
2016 and Prior |  | 33,631 |
Total loans, net of fair value hedge basis point adjustments | 100,876 | 73,237 |
Commercial real estate ("CRE") |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 417,973 |  |
2022/2021 | 1,019,518 | 1,024,486 |
2021/2020 | 837,194 | 854,391 |
2020/2019 | 715,891 | 777,757 |
2019/2018 | 502,703 | 522,932 |
2018/2017 and Prior | 1,073,382 | 323,768 |
2016 and Prior |  | 895,167 |
Revolving | 24,839 | 34,362 |
Revolving-Term | 29,400 | 24,767 |
Total loans, net of fair value hedge basis point adjustments | 4,620,900 | 4,457,630 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs |  |  | 3,406
Commercial real estate ("CRE") | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 417,973 |  |
2022/2021 | 990,748 | 1,021,622 |
2021/2020 | 817,171 | 854,240 |
2020/2019 | 566,427 | 753,552 |
2019/2018 | 484,930 | 510,332 |
2018/2017 and Prior | 1,025,160 | 308,265 |
2016 and Prior |  | 868,099 |
Revolving | 24,839 | 34,362 |
Revolving-Term | 11,538 | 24,767 |
Total loans, net of fair value hedge basis point adjustments | 4,338,786 | 4,375,239 |
Commercial real estate ("CRE") | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 | 28,770 | 2,864 |
2021/2020 | 19,872 |  |
2020/2019 | 88,040 | 19,655 |
2019/2018 | 10,484 | 4,653 |
2018/2017 and Prior | 5,754 | 14,372 |
2016 and Prior |  | 15,478 |
Revolving-Term | 17,862 |  |
Total loans, net of fair value hedge basis point adjustments | 170,782 | 57,022 |
Commercial real estate ("CRE") | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2021/2020 | 151 | 151 |
2020/2019 | 61,424 | 4,550 |
2019/2018 | 7,289 | 7,947 |
2018/2017 and Prior | 42,468 | 1,131 |
2016 and Prior |  | 11,590 |
Total loans, net of fair value hedge basis point adjustments | 111,332 | 25,369 |
Acquisition, development, and construction ("ADC") |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 16,735 |  |
2022/2021 | 29,034 | 36,877 |
2021/2020 | 74,163 | 153,200 |
2020/2019 | 9,900 | 11,242 |
2019/2018 | 14,918 | 15,943 |
2018/2017 and Prior | 437 |  |
2016 and Prior |  | 2,087 |
Revolving | 22,444 | 10,033 |
Revolving-Term | 882 | 281 |
Total loans, net of fair value hedge basis point adjustments | 168,513 | 229,663 |
Acquisition, development, and construction ("ADC") | Pass |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 16,735 |  |
2022/2021 | 17,534 | 36,877 |
2021/2020 | 59,202 | 152,543 |
2020/2019 | 9,900 | 11,242 |
2019/2018 | 2,665 | 15,943 |
2018/2017 and Prior | 437 |  |
2016 and Prior |  | 2,087 |
Revolving | 22,444 | 10,033 |
Revolving-Term | 225 | 281 |
Total loans, net of fair value hedge basis point adjustments | 129,142 | 229,006 |
Acquisition, development, and construction ("ADC") | Special Mention |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2022/2021 | 11,500 |  |
2021/2020 | 14,961 |  |
2019/2018 | 12,253 |  |
Total loans, net of fair value hedge basis point adjustments | 38,714 |  |
Acquisition, development, and construction ("ADC") | Substandard |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2021/2020 |  | 657 |
Revolving-Term | 657 |  |
Total loans, net of fair value hedge basis point adjustments | 657 | 657 |
Other Loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments | 5,755 | 7,679 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs | 300 | 53 | $ 777
Other Loans | Credit Risk Profile |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments | 5,755 | 7,679 |
Other Loans | Performing | Credit Risk Profile |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments | 5,755 | 7,580 |
Other Loans | Non-Accrual | Credit Risk Profile |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
Total loans, net of fair value hedge basis point adjustments |  | $ 99 |
Excludes Other Loans |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |
2023/2022 | 923,383 |  |
2022/2021 | 2,755,142 |  |
2021/2020 | 1,629,836 |  |
2020/2019 | 1,144,485 |  |
2019/2018 | 1,002,340 |  |
2018/2017 and Prior | 2,458,637 |  |
Revolving | 740,962 |  |
Revolving-Term | 106,297 |  |
Total loans, net of fair value hedge basis point adjustments | 10,761,082 |  |
Excludes Other Loans | Total real estate loans |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |
YTD Gross Charge-Offs 2021/2020 | 77 |  |
YTD Gross Charge-Offs 2020/2019 | 38 |  |
YTD Gross Charge-Offs 2019/2018 | 4,166 |  |
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior | 2,231 |  |
YTD Gross Charge-Offs Revolving | 5,464 |  |
YTD Gross Charge-Offs Revolving-Term | 3,404 |  |
YTD Gross Charge-Offs | $ 15,380 |  |

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