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LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Percentage of aggregate rental income | 50.00% |
Loans | $ 10,506,098 | $ 5,622,044
2021 | 879,616 |
2020 | 2,373,222 |
2019 | 1,360,228 |
2018 | 830,392 |
2017 | 1,124,441 |
2016 and Prior | 3,043,267 |
Revolving | 724,519 |
Revolving-Term | 146,004 |
Total | 10,481,689 |
One-to-four family residential and cooperative/condominium apartment |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 30,658 |
2020 | 102,503 |
2019 | 97,118 |
2018 | 105,785 |
2017 | 101,472 |
2016 and Prior | 188,043 |
Revolving | 55,025 |
Revolving-Term | 15,811 |
Total | 696,415 |
One-to-four family residential and cooperative/condominium apartment | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 30,658 |
2020 | 102,503 |
2019 | 95,992 |
2018 | 105,587 |
2017 | 101,101 |
2016 and Prior | 177,780 |
Revolving | 54,179 |
Revolving-Term | 13,426 |
Total | 681,226 |
One-to-four family residential and cooperative/condominium apartment | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 | 381 |
2018 | 152 |
2017 | 371 |
2016 and Prior | 5,106 |
Revolving | 846 |
Revolving-Term | 1,106 |
Total | 7,962 |
One-to-four family residential and cooperative/condominium apartment | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 | 745 |
2018 | 46 |
2016 and Prior | 5,157 |
Revolving-Term | 1,279 |
Total | 7,227 |
Multifamily residential and residential mixed-use |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 95,876 |
2020 | 365,073 |
2019 | 554,328 |
2018 | 242,739 |
2017 | 514,157 |
2016 and Prior | 1,784,829 |
Revolving | 10,194 |
Revolving-Term | 11 |
Total | 3,567,207 |
Multifamily residential and residential mixed-use | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 95,876 |
2020 | 365,073 |
2019 | 518,902 |
2018 | 215,459 |
2017 | 464,424 |
2016 and Prior | 1,672,655 |
Revolving | 9,698 |
Revolving-Term | 11 |
Total | 3,342,098 |
Multifamily residential and residential mixed-use | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 | 1,005 |
2017 | 17,169 |
2016 and Prior | 17,057 |
Total | 35,231 |
Multifamily residential and residential mixed-use | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 | 34,421 |
2018 | 27,280 |
2017 | 32,564 |
2016 and Prior | 95,117 |
Revolving | 496 |
Total | 189,878 |
Commercial real estate ("CRE") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 184,029 |
2020 | 872,325 |
2019 | 610,966 |
2018 | 419,212 |
2017 | 440,167 |
2016 and Prior | 1,028,085 |
Revolving | 50,050 |
Revolving-Term | 26,453 |
Total | 3,631,287 |
Commercial real estate ("CRE") | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 184,029 |
2020 | 867,480 |
2019 | 604,893 |
2018 | 396,946 |
2017 | 404,571 |
2016 and Prior | 978,940 |
Revolving | 50,050 |
Revolving-Term | 26,440 |
Total | 3,513,349 |
Commercial real estate ("CRE") | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 4,256 |
2019 | 2,673 |
2018 | 9,031 |
2017 | 13,536 |
2016 and Prior | 11,578 |
Total | 41,074 |
Commercial real estate ("CRE") | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 589 |
2019 | 3,400 |
2018 | 13,235 |
2017 | 22,060 |
2016 and Prior | 37,567 |
Revolving-Term | 10 |
Total | 76,861 |
Commercial real estate ("CRE") | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Revolving-Term | 3 |
Total | 3 |
Acquisition, development, and construction ("ADC") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 8,105 |
2020 | 39,106 |
2019 | 23,599 |
2018 | 11,597 |
2017 | 5,615 |
2016 and Prior | 1,460 |
Revolving | 121,537 |
Revolving-Term | 43,151 |
Total | 254,170 |
Acquisition, development, and construction ("ADC") | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 8,105 |
2020 | 39,106 |
2019 | 23,599 |
2018 | 10,520 |
2017 | 5,615 |
2016 and Prior | 1,355 |
Revolving | 121,537 |
Revolving-Term | 29,651 |
Total | 239,488 |
Acquisition, development, and construction ("ADC") | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2018 | 1,077 |
Revolving-Term | 13,500 |
Total | 14,577 |
Acquisition, development, and construction ("ADC") | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2016 and Prior | 105 |
Total | 105 |
C&I [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 560,948 |
2020 | 994,215 |
2019 | 74,217 |
2018 | 51,059 |
2017 | 63,030 |
2016 and Prior | 40,850 |
Revolving | 487,713 |
Revolving-Term | 60,578 |
Total | 2,332,610 |
C&I [Member] | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2021 | 560,948 |
2020 | 991,821 |
2019 | 71,898 |
2018 | 44,089 |
2017 | 47,108 |
2016 and Prior | 38,787 |
Revolving | 461,029 |
Revolving-Term | 42,082 |
Total | 2,257,762 |
C&I [Member] | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 2,345 |
2019 | 1,270 |
2018 | 5,553 |
2017 | 765 |
2016 and Prior | 559 |
Revolving | 22,566 |
Revolving-Term | 3,078 |
Total | 36,136 |
C&I [Member] | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2020 | 49 |
2019 | 839 |
2018 | 1,417 |
2017 | 3,228 |
2016 and Prior | 1,314 |
Revolving | 4,118 |
Revolving-Term | 15,190 |
Total | 26,155 |
C&I [Member] | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
2019 | 210 |
2017 | 11,929 |
2016 and Prior | 190 |
Revolving-Term | 228 |
Total | 12,557 |
Real estate |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 8,149,079 | 4,978,195
Real estate | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 4,681,059
Real estate | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 83,761
Real estate | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 213,375
Real estate | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | One-to-four family residential and cooperative/condominium apartment |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 696,415 | 184,989
Real estate | One-to-four family residential and cooperative/condominium apartment | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 183,293
Real estate | One-to-four family residential and cooperative/condominium apartment | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | One-to-four family residential and cooperative/condominium apartment | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 1,696
Real estate | One-to-four family residential and cooperative/condominium apartment | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | Multifamily residential and residential mixed-use |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 3,567,207 | 2,758,743
Real estate | Multifamily residential and residential mixed-use | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 2,523,258
Real estate | Multifamily residential and residential mixed-use | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 56,400
Real estate | Multifamily residential and residential mixed-use | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 179,085
Real estate | Multifamily residential and residential mixed-use | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | Commercial real estate ("CRE") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 3,631,287 | 1,878,167
Real estate | Commercial real estate ("CRE") | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 1,831,712
Real estate | Commercial real estate ("CRE") | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 13,861
Real estate | Commercial real estate ("CRE") | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 32,594
Real estate | Commercial real estate ("CRE") | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | Acquisition, development, and construction ("ADC") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 254,170 | 156,296
Real estate | Acquisition, development, and construction ("ADC") | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 142,796
Real estate | Acquisition, development, and construction ("ADC") | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 13,500
Real estate | Acquisition, development, and construction ("ADC") | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Real estate | Acquisition, development, and construction ("ADC") | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 0
Commercial and industrial ("C&I") |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 2,332,610 | 641,533
Commercial and industrial ("C&I"), including SBA and PPP loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 2,332,610 | 641,533
Commercial and industrial ("C&I"), including SBA and PPP loans | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 613,691
Commercial and industrial ("C&I"), including SBA and PPP loans | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 2,131
Commercial and industrial ("C&I"), including SBA and PPP loans | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 13,315
Commercial and industrial ("C&I"), including SBA and PPP loans | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 12,396
Real Estate Loans and C & I Loans [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 5,619,728
Real Estate Loans and C & I Loans [Member] | Pass [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 5,294,750
Real Estate Loans and C & I Loans [Member] | Special Mention [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 85,892
Real Estate Loans and C & I Loans [Member] | Substandard [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 226,690
Real Estate Loans and C & I Loans [Member] | Doubtful [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 12,396
Other loans |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 24,409 | 2,316
Other loans | Credit Risk Profile [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 24,409 |
Other loans | Performing [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | 2,315
Other loans | Performing [Member] | Credit Risk Profile [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | 24,310 |
Other loans | Non-Accrual [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans |  | $ 1
Other loans | Non-Accrual [Member] | Credit Risk Profile [Member] |  |
Credit Risk Profile of Real Estate Loans [Abstract] |  |
Loans | $ 99 |

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