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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | $ 10,850,611 |  | $ 10,850,611 |  | $ 10,566,831
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 |  |  | 2,231 |  | 2,414
YTD Gross Charge-Offs Revolving |  |  | 1,021 |  | 1,460
YTD Gross Charge-Offs Revolving-Term |  |  | 3,404 |  | 242
YTD Gross Charge-Offs |  |  | 10,937 |  | 11,401
Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 808,171 |  | 808,171 |  |
2022/2021 | 2,793,493 |  | 2,793,493 |  | 2,845,428
2021/2020 | 1,640,908 |  | 1,640,908 |  | 1,733,872
2020/2019 | 1,009,045 |  | 1,009,045 |  | 1,196,053
2019/2018 | 986,544 |  | 986,544 |  | 1,024,753
2018/2017 and Prior | 2,401,398 |  | 2,401,398 |  | 522,005
2016 and Prior |  |  |  |  | 2,175,148
Revolving | 721,788 |  | 721,788 |  | 726,712
Revolving-Term | 64,405 |  | 64,405 |  | 59,849
Total Loans | 10,425,752 |  | 10,425,752 |  | 10,283,820
Special Mention |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 506 |  | 506 |  |
2022/2021 | 3,184 |  | 3,184 |  | 6,634
2021/2020 | 20,459 |  | 20,459 |  |
2020/2019 | 101,118 |  | 101,118 |  | 20,549
2019/2018 | 13,340 |  | 13,340 |  | 17,364
2018/2017 and Prior | 59,530 |  | 59,530 |  | 16,628
2016 and Prior |  |  |  |  | 31,664
Revolving | 23,121 |  | 23,121 |  | 9,641
Revolving-Term | 9,835 |  | 9,835 |  | 1,204
Total Loans | 231,093 |  | 231,093 |  | 103,684
Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 1 |  | 1 |  |
2022/2021 | 1,950 |  | 1,950 |  | 5,242
2021/2020 | 3,118 |  | 3,118 |  | 2,052
2020/2019 | 44,251 |  | 44,251 |  | 23,233
2019/2018 | 15,349 |  | 15,349 |  | 19,143
2018/2017 and Prior | 100,553 |  | 100,553 |  | 22,819
2016 and Prior |  |  |  |  | 66,232
Revolving | 8,290 |  | 8,290 |  | 11,290
Revolving-Term | 9,072 |  | 9,072 |  | 10,505
Total Loans | 182,584 |  | 182,584 |  | 160,516
Doubtful |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2019/2018 | 4,166 |  | 4,166 |  | 8,332
2018/2017 and Prior | 749 |  | 749 |  | 752
2016 and Prior |  |  |  |  | 2,048
Total Loans | 4,915 |  | 4,915 |  | 11,132
Excludes Other Loans |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 808,678 |  | 808,678 |  |
2022/2021 | 2,798,627 |  | 2,798,627 |  | 2,857,304
2021/2020 | 1,664,485 |  | 1,664,485 |  | 1,735,924
2020/2019 | 1,154,414 |  | 1,154,414 |  | 1,239,835
2019/2018 | 1,019,399 |  | 1,019,399 |  | 1,069,592
2018/2017 and Prior | 2,562,230 |  | 2,562,230 |  | 562,204
2016 and Prior |  |  |  |  | 2,275,092
Revolving | 753,199 |  | 753,199 |  | 747,643
Revolving-Term | 83,312 |  | 83,312 |  | 71,558
Total Loans | 10,844,344 |  | 10,844,344 |  | 10,559,152
Business loans |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 198,338 |  | 198,338 |  |
2022/2021 | 433,722 |  | 433,722 |  | 461,575
2021/2020 | 203,331 |  | 203,331 |  | 229,523
2020/2019 | 175,594 |  | 175,594 |  | 197,259
2019/2018 | 170,837 |  | 170,837 |  | 188,094
2018/2017 and Prior | 361,288 |  | 361,288 |  | 149,322
2016 and Prior |  |  |  |  | 261,330
Revolving | 672,232 |  | 672,232 |  | 671,312
Revolving-Term | 56,426 |  | 56,426 |  | 53,442
Total Loans | 2,271,768 |  | 2,271,768 |  | 2,211,857
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 |  |  | 1,021 |  | 1,460
YTD Gross Charge-Offs Revolving-Term |  |  | 3,390 |  | 242
YTD Gross Charge-Offs | 5,147 | $ 5,462 | 10,921 | $ 8,742 | 11,401
Business loans | Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 197,831 |  | 197,831 |  |
2022/2021 | 428,588 |  | 428,588 |  | 449,699
2021/2020 | 199,606 |  | 199,606 |  | 228,143
2020/2019 | 167,826 |  | 167,826 |  | 187,522
2019/2018 | 159,084 |  | 159,084 |  | 173,527
2018/2017 and Prior | 316,910 |  | 316,910 |  | 130,576
2016 and Prior |  |  |  |  | 240,131
Revolving | 640,980 |  | 640,980 |  | 650,960
Revolving-Term | 39,015 |  | 39,015 |  | 43,552
Total Loans | 2,149,840 |  | 2,149,840 |  | 2,104,110
Business loans | Special Mention |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 506 |  | 506 |  |
2022/2021 | 3,184 |  | 3,184 |  | 6,634
2021/2020 | 1,279 |  | 1,279 |  |
2020/2019 | 923 |  | 923 |  | 894
2019/2018 | 4,850 |  | 4,850 |  | 1,529
2018/2017 and Prior | 13,541 |  | 13,541 |  | 15,893
2016 and Prior |  |  |  |  | 4,213
Revolving | 22,962 |  | 22,962 |  | 9,062
Revolving-Term | 9,125 |  | 9,125 |  | 478
Total Loans | 56,370 |  | 56,370 |  | 38,703
Business loans | Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 1 |  | 1 |  |
2022/2021 | 1,950 |  | 1,950 |  | 5,242
2021/2020 | 2,446 |  | 2,446 |  | 1,380
2020/2019 | 6,845 |  | 6,845 |  | 8,843
2019/2018 | 2,737 |  | 2,737 |  | 4,706
2018/2017 and Prior | 30,088 |  | 30,088 |  | 2,101
2016 and Prior |  |  |  |  | 14,938
Revolving | 8,290 |  | 8,290 |  | 11,290
Revolving-Term | 8,286 |  | 8,286 |  | 9,412
Total Loans | 60,643 |  | 60,643 |  | 57,912
Business loans | Doubtful |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2019/2018 | 4,166 |  | 4,166 |  | 8,332
2018/2017 and Prior | 749 |  | 749 |  | 752
2016 and Prior |  |  |  |  | 2,048
Total Loans | 4,915 |  | 4,915 |  | 11,132
One-to-four family residential and cooperative/condominium apartment |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 161,750 |  | 161,750 |  |
2022/2021 | 217,184 |  | 217,184 |  | 225,031
2021/2020 | 103,310 |  | 103,310 |  | 108,185
2020/2019 | 70,929 |  | 70,929 |  | 73,758
2019/2018 | 64,517 |  | 64,517 |  | 66,742
2018/2017 and Prior | 227,440 |  | 227,440 |  | 67,180
2016 and Prior |  |  |  |  | 176,292
Revolving | 33,418 |  | 33,418 |  | 41,751
Revolving-Term | 14,321 |  | 14,321 |  | 14,382
Total Loans | 892,869 |  | 892,869 |  | 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 |  |
One-to-four family residential and cooperative/condominium apartment | Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 161,750 |  | 161,750 |  |
2022/2021 | 217,184 |  | 217,184 |  | 225,031
2021/2020 | 103,310 |  | 103,310 |  | 108,185
2020/2019 | 69,919 |  | 69,919 |  | 72,732
2019/2018 | 63,299 |  | 63,299 |  | 65,515
2018/2017 and Prior | 215,385 |  | 215,385 |  | 66,038
2016 and Prior |  |  |  |  | 164,338
Revolving | 33,259 |  | 33,259 |  | 41,172
Revolving-Term | 12,825 |  | 12,825 |  | 12,563
Total Loans | 876,931 |  | 876,931 |  | 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 | 756 |  | 756 |  | 735
2016 and Prior |  |  |  |  | 1,175
Revolving | 159 |  | 159 |  | 579
Revolving-Term | 710 |  | 710 |  | 726
Total Loans | 1,625 |  | 1,625 |  | 3,215
One-to-four family residential and cooperative/condominium apartment | Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2020/2019 | 1,010 |  | 1,010 |  | 1,026
2019/2018 | 1,218 |  | 1,218 |  | 1,227
2018/2017 and Prior | 11,299 |  | 11,299 |  | 407
2016 and Prior |  |  |  |  | 10,779
Revolving-Term | 786 |  | 786 |  | 1,093
Total Loans | 14,313 |  | 14,313 |  | 14,532
Multifamily residential and residential mixed-use |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 244,041 |  | 244,041 |  |
2022/2021 | 1,367,753 |  | 1,367,753 |  | 1,386,549
2021/2020 | 593,271 |  | 593,271 |  | 582,393
2020/2019 | 318,024 |  | 318,024 |  | 328,718
2019/2018 | 398,615 |  | 398,615 |  | 414,117
2018/2017 and Prior | 1,163,265 |  | 1,163,265 |  | 147,385
2016 and Prior |  |  |  |  | 1,155,080
Revolving | 12,715 |  | 12,715 |  | 12,584
Revolving-Term | 4,340 |  | 4,340 |  |
Total Loans | 4,102,024 |  | 4,102,024 |  | 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 |  | 2 |  |
Multifamily residential and residential mixed-use | Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 244,041 |  | 244,041 |  |
2022/2021 | 1,367,753 |  | 1,367,753 |  | 1,386,549
2021/2020 | 589,048 |  | 589,048 |  | 582,393
2020/2019 | 285,272 |  | 285,272 |  | 316,424
2019/2018 | 389,601 |  | 389,601 |  | 395,933
2018/2017 and Prior | 1,086,015 |  | 1,086,015 |  | 127,074
2016 and Prior |  |  |  |  | 1,107,281
Revolving | 12,715 |  | 12,715 |  | 12,584
Revolving-Term | 4,340 |  | 4,340 |  |
Total Loans | 3,978,785 |  | 3,978,785 |  | 3,928,238
Multifamily residential and residential mixed-use | Special Mention |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2021/2020 | 4,223 |  | 4,223 |  |
2020/2019 | 22,096 |  | 22,096 |  |
2019/2018 | 3,905 |  | 3,905 |  | 11,183
2018/2017 and Prior | 30,476 |  | 30,476 |  |
2016 and Prior |  |  |  |  | 14,168
Total Loans | 60,700 |  | 60,700 |  | 25,351
Multifamily residential and residential mixed-use | Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2020/2019 | 10,656 |  | 10,656 |  | 12,294
2019/2018 | 5,109 |  | 5,109 |  | 7,001
2018/2017 and Prior | 46,774 |  | 46,774 |  | 20,311
2016 and Prior |  |  |  |  | 33,631
Total Loans | 62,539 |  | 62,539 |  | 73,237
Non-owner-occupied commercial real estate |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 196,881 |  | 196,881 |  |
2022/2021 | 728,514 |  | 728,514 |  | 747,272
2021/2020 | 667,914 |  | 667,914 |  | 662,623
2020/2019 | 582,220 |  | 582,220 |  | 628,858
2019/2018 | 369,786 |  | 369,786 |  | 384,696
2018/2017 and Prior | 809,742 |  | 809,742 |  | 198,317
2016 and Prior |  |  |  |  | 680,303
Revolving | 11,237 |  | 11,237 |  | 11,963
Revolving-Term | 7,987 |  | 7,987 |  | 3,453
Total Loans | 3,374,281 |  | 3,374,281 |  | 3,317,485
Non-owner-occupied commercial real estate | Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 196,881 |  | 196,881 |  |
2022/2021 | 728,514 |  | 728,514 |  | 747,272
2021/2020 | 667,899 |  | 667,899 |  | 662,608
2020/2019 | 478,381 |  | 478,381 |  | 608,133
2019/2018 | 358,916 |  | 358,916 |  | 373,835
2018/2017 and Prior | 782,593 |  | 782,593 |  | 198,317
2016 and Prior |  |  |  |  | 661,311
Revolving | 11,237 |  | 11,237 |  | 11,963
Revolving-Term | 7,987 |  | 7,987 |  | 3,453
Total Loans | 3,232,408 |  | 3,232,408 |  | 3,266,892
Non-owner-occupied commercial real estate | Special Mention |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2020/2019 | 78,099 |  | 78,099 |  | 19,655
2019/2018 | 4,585 |  | 4,585 |  | 4,652
2018/2017 and Prior | 14,757 |  | 14,757 |  |
2016 and Prior |  |  |  |  | 12,108
Total Loans | 97,441 |  | 97,441 |  | 36,415
Non-owner-occupied commercial real estate | Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2021/2020 | 15 |  | 15 |  | 15
2020/2019 | 25,740 |  | 25,740 |  | 1,070
2019/2018 | 6,285 |  | 6,285 |  | 6,209
2018/2017 and Prior | 12,392 |  | 12,392 |  |
2016 and Prior |  |  |  |  | 6,884
Total Loans | 44,432 |  | 44,432 |  | 14,178
Non-owner-occupied commercial real estate | Total real estate loans |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | 3,374,281 |  | 3,374,281 |  | 3,317,485
Acquisition, development, and construction ("ADC") |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 7,668 |  | 7,668 |  |
2022/2021 | 51,454 |  | 51,454 |  | 36,877
2021/2020 | 96,659 |  | 96,659 |  | 153,200
2020/2019 | 7,647 |  | 7,647 |  | 11,242
2019/2018 | 15,644 |  | 15,644 |  | 15,943
2018/2017 and Prior | 495 |  | 495 |  |
2016 and Prior |  |  |  |  | 2,087
Revolving | 23,597 |  | 23,597 |  | 10,033
Revolving-Term | 238 |  | 238 |  | 281
Total Loans | 203,402 |  | 203,402 |  | 229,663
Acquisition, development, and construction ("ADC") | Pass |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2023/2022 | 7,668 |  | 7,668 |  |
2022/2021 | 51,454 |  | 51,454 |  | 36,877
2021/2020 | 81,045 |  | 81,045 |  | 152,543
2020/2019 | 7,647 |  | 7,647 |  | 11,242
2019/2018 | 15,644 |  | 15,644 |  | 15,943
2018/2017 and Prior | 495 |  | 495 |  |
2016 and Prior |  |  |  |  | 2,087
Revolving | 23,597 |  | 23,597 |  | 10,033
Revolving-Term | 238 |  | 238 |  | 281
Total Loans | 187,788 |  | 187,788 |  | 229,006
Acquisition, development, and construction ("ADC") | Special Mention |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2021/2020 | 14,957 |  | 14,957 |  |
Total Loans | 14,957 |  | 14,957 |  |
Acquisition, development, and construction ("ADC") | Substandard |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
2021/2020 | 657 |  | 657 |  | 657
Total Loans | 657 |  | 657 |  | 657
Other Loans |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | 6,267 |  | 6,267 |  | 7,679
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] |  |  |  |  |
YTD Gross Charge-Offs | 26 | $ 49 | 60 | $ 52 |
Other Loans | Credit Risk Profile |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | 6,267 |  | 6,267 |  | 7,679
Other Loans | Performing | Credit Risk Profile |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | 6,048 |  | 6,048 |  | 7,580
Other Loans | Non-Accrual | Credit Risk Profile |  |  |  |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |  |  |  |
Total Loans | $ 219 |  | $ 219 |  | $ 99

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