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LOANS HELD FOR INVESTMENT, NET - Deferral Loans (Details) $ in Thousands | Mar. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($)
--- | --- | ---
CARES Act Loan [Abstract] |  |  |
Balance |  | $ 10,506,098 | $ 5,622,044
COVID-19 [Member] |  |  |
CARES Act Loan [Abstract] |  |  |
Number of loans | loan |  | 34 |
Balance | [1] | $ 66,654 |
% of portfolio |  | 0.60% |
One-to-four family residential and cooperative/condominium apartment | COVID-19 [Member] |  |  |
CARES Act Loan [Abstract] |  |  |
Number of loans | loan |  | 15 |
Balance | [1] | $ 15,489 |
% of portfolio |  | 2.20% |
Commercial real estate ("CRE") | COVID-19 [Member] |  |  |
CARES Act Loan [Abstract] |  |  |
Number of loans | loan |  | 8 |
Balance | [1] | $ 24,174 |
% of portfolio |  | 0.70% |
Acquisition, development, and construction ("ADC") | COVID-19 [Member] |  |  |
CARES Act Loan [Abstract] |  |  |
Number of loans | loan |  | 1 |
Balance | [1] | $ 13,500 |
% of portfolio |  | 5.30% |
Real estate |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | $ 8,149,079 | 4,978,195
Real estate | One-to-four family residential and cooperative/condominium apartment |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | 696,415 | 184,989
Real estate | Multifamily residential and residential mixed-use |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | 3,567,207 | 2,758,743
Real estate | Commercial real estate ("CRE") |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | 3,631,287 | 1,878,167
Real estate | Acquisition, development, and construction ("ADC") |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | 254,170 | 156,296
Commercial and industrial ("C&I") |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | 2,332,610 | 641,533
Commercial and industrial ("C&I"), including SBA and PPP loans |  |  |
CARES Act Loan [Abstract] |  |  |
Balance |  | $ 2,332,610 | $ 641,533
Commercial and industrial ("C&I"), including SBA and PPP loans | COVID-19 [Member] |  |  |
CARES Act Loan [Abstract] |  |  |
Number of loans | loan |  | 10 |
Balance | [1] | $ 13,491 |
% of portfolio |  | 0.60% |
[1] | Amount excludes net deferred costs due to immateriality.

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- References No definition available. + Details
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- Definition The number of loans approved for deferral by bank due to COVID-19 pandemic. + References No definition available. + Details
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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522 + Details
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