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LOANS HELD FOR INVESTMENT, NET - Allowance for Credit Losses Activity (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | $ 41,461 | $ 28,441 | $ 21,782
PCD Day 1 | 52,284 |  |
Provision (credit) for credit loss expense | 3,303 | 26,165 | 17,340
Charge-offs | (9,578) | (13,309) | (10,705)
Recoveries | 302 | 164 | 24
Ending balance | 83,853 | 41,461 | 28,441
Non-accrual with No Allowance | 1,649 |  |
Non-accrual with Allowance | 38,658 |  |
Reserve | 19,409 |  |
Allowance for loan losses: |  |  |
Individually evaluated for impairment | 22,300 | 6,474 |
Collectively evaluated for impairment | 41,400 | 34,987 |
Total ending allowance balance | 83,853 | 41,461 | 28,441
Loans: |  |  |
Individually evaluated for impairment | 51,400 | 17,069 |
Collectively evaluated for impairment | 8,980,000 | 5,604,975 |
Total ending loans balance |  | 5,622,044 |
Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | (3,919) |  |
Ending balance |  | (3,919) |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | (3,919) |
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 37,542 |  |
Ending balance |  | 37,542 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 37,542 |
Total real estate loans |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 28,712 | 15,555 | 17,818
PCD Day 1 | 28,753 |  |
Provision (credit) for credit loss expense | (4,077) | 16,234 | (2,034)
Charge-offs | (3,817) | (3,207) | (250)
Recoveries | 176 | 130 | 21
Ending balance | 47,771 | 28,712 | 15,555
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 28,712 |
Total ending allowance balance | 47,771 | 28,712 | 15,555
Loans: |  |  |
Individually evaluated for impairment |  | 4,567 |
Collectively evaluated for impairment |  | 4,973,628 |
Total ending loans balance |  | 4,978,195 |
Total real estate loans | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | (1,976) |  |
Ending balance |  | (1,976) |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | (1,976) |
Total real estate loans | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 26,736 |  |
Ending balance |  | 26,736 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 26,736 |
One-to-four family residential and cooperative/condominium apartment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 644 | 269 | 198
PCD Day 1 | 2,220 |  |
Provision (credit) for credit loss expense | 1,975 | 386 | 86
Charge-offs | (20) | (11) | (22)
Recoveries | 65 |  | 7
Ending balance | 5,932 | 644 | 269
Non-accrual with Allowance | 7,623 |  |
Reserve | 1,278 |  |
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 644 |
Total ending allowance balance | 5,932 | 644 | 269
Loans: |  |  |
Collectively evaluated for impairment |  | 184,989 |
Total ending loans balance |  | 184,989 |
One-to-four family residential and cooperative/condominium apartment | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 1,048 |  |
Ending balance |  | 1,048 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 1,048 |
One-to-four family residential and cooperative/condominium apartment | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 1,692 |  |
Ending balance |  | 1,692 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 1,692 |
Multifamily residential and residential mixed-use |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 17,016 | 10,142 | 13,446
PCD Day 1 | 3,292 |  |
Provision (credit) for credit loss expense | (3,921) | 9,934 | (3,233)
Charge-offs | (391) | (3,190) | (83)
Recoveries | 74 | 130 | 12
Ending balance | 7,816 | 17,016 | 10,142
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 17,016 |
Total ending allowance balance | 7,816 | 17,016 | 10,142
Loans: |  |  |
Individually evaluated for impairment |  | 1,863 |
Collectively evaluated for impairment |  | 2,756,880 |
Total ending loans balance |  | 2,758,743 |
Multifamily residential and residential mixed-use | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | (8,254) |  |
Ending balance |  | (8,254) |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | (8,254) |
Multifamily residential and residential mixed-use | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 8,762 |  |
Ending balance |  | 8,762 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 8,762 |
Acquisition, development, and construction ("ADC") |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 1,993 | 1,244 | 397
PCD Day 1 | 117 |  |
Provision (credit) for credit loss expense | 2,366 | 749 | 847
Ending balance | 4,857 | 1,993 | 1,244
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 1,993 |
Total ending allowance balance | 4,857 | 1,993 | 1,244
Loans: |  |  |
Collectively evaluated for impairment |  | 156,296 |
Total ending loans balance |  | 156,296 |
Acquisition, development, and construction ("ADC") | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 381 |  |
Ending balance |  | 381 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 381 |
Acquisition, development, and construction ("ADC") | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 2,374 |  |
Ending balance |  | 2,374 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 2,374 |
Commercial real estate ("CRE") |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 9,059 | 3,900 | 3,777
PCD Day 1 | 23,124 |  |
Provision (credit) for credit loss expense | (4,497) | 5,165 | 266
Charge-offs | (3,406) | (6) | (145)
Recoveries | 37 |  | 2
Ending balance | 29,166 | 9,059 | 3,900
Non-accrual with No Allowance | 1,301 |  |
Non-accrual with Allowance | 3,752 |  |
Reserve | 797 |  |
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 9,059 |
Total ending allowance balance | 29,166 | 9,059 | 3,900
Loans: |  |  |
Individually evaluated for impairment |  | 2,704 |
Collectively evaluated for impairment |  | 1,875,463 |
Total ending loans balance |  | 1,878,167 |
Commercial real estate ("CRE") | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 4,849 |  |
Ending balance |  | 4,849 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 4,849 |
Commercial real estate ("CRE") | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 13,908 |  |
Ending balance |  | 13,908 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 13,908 |
Commercial and Industrial ("C&I") Loans |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 12,737 | 12,870 | 3,946
PCD Day 1 | 23,374 |  |
Provision (credit) for credit loss expense | 6,016 | 9,928 | 19,368
Charge-offs | (4,984) | (10,095) | (10,447)
Recoveries | 123 | 34 | 3
Ending balance | 35,331 | 12,737 | 12,870
Non-accrual with No Allowance | 348 |  |
Non-accrual with Allowance | 26,918 |  |
Reserve | 16,973 |  |
Allowance for loan losses: |  |  |
Individually evaluated for impairment |  | 6,474 |
Collectively evaluated for impairment |  | 6,263 |
Total ending allowance balance | 35,331 | 12,737 | 12,870
Loans: |  |  |
Individually evaluated for impairment |  | 12,502 |
Collectively evaluated for impairment |  | 629,031 |
Total ending loans balance |  | 641,533 |
Commercial and Industrial ("C&I") Loans | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | (1,935) |  |
Ending balance |  | (1,935) |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | (1,935) |
Commercial and Industrial ("C&I") Loans | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 10,802 |  |
Ending balance |  | 10,802 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | 10,802 |
Other Loans |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 12 | 16 | 18
PCD Day 1 | 157 |  |
Provision (credit) for credit loss expense | 1,364 | 3 | 6
Charge-offs | (777) | (7) | (8)
Recoveries | 3 |  |
Ending balance | 751 | 12 | 16
Non-accrual with Allowance | 365 |  |
Reserve | 361 |  |
Allowance for loan losses: |  |  |
Collectively evaluated for impairment |  | 12 |
Total ending allowance balance | 751 | 12 | $ 16
Loans: |  |  |
Collectively evaluated for impairment |  | 2,316 |
Total ending loans balance |  | 2,316 |
Other Loans | Cumulative Effect, Period of Adoption, Adjustment |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | (8) |  |
Ending balance |  | (8) |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | (8) |
Other Loans | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | $ 4 |  |
Ending balance |  | 4 |
Allowance for loan losses: |  |  |
Total ending allowance balance |  | $ 4 |

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