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Loans - Details and Delinquency Status of Nonperforming Loans (detail, and delinquency status, of non-performing loans (Non-Accrual Loans and Loans Past Due 90 Days or More and Still Accruing) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | $ 3,806,617 | $ 3,823,238
Non-accrual loans | 7,622 |
90 Days or More Past Due and Accruing | 384 | 1,100
Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual loans | 1,882 |
Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual loans | 5,117 |
Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual loans | 314 |
Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual loans | 281 |
Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual loans | 28 |
Non-Performing Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 8,006 | 9,629
Non-accrual loans | 7,622 | 8,516
90 Days or More Past Due and Accruing | 384 | 1,113
Non-Performing Loans | Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 7,906 | 9,153
Non-accrual loans | 7,594 | 8,479
90 Days or More Past Due and Accruing | 312 | 674
Non-Performing Loans | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 1,882 | 1,153
Non-accrual loans | 1,882 | 1,153
90 Days or More Past Due and Accruing | 0 | 0
Non-Performing Loans | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 5,264 | 6,729
Non-accrual loans | 5,117 | 6,229
90 Days or More Past Due and Accruing | 147 | 500
Non-Performing Loans | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 479 | 1,080
Non-accrual loans | 314 | 906
90 Days or More Past Due and Accruing | 165 | 174
Non-Performing Loans | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 281 | 191
Non-accrual loans | 281 | 191
90 Days or More Past Due and Accruing | 0 | 0
Non-Performing Loans | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 100 | 473
Non-accrual loans | 28 | 37
90 Days or More Past Due and Accruing | 72 | 436
Non-Performing Loans | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 3
Non-accrual loans |  | 0
90 Days or More Past Due and Accruing |  | 3
Non-Performing Loans | Substandard | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 1,882 | 1,153
Non-accrual loans | 1,882 | 1,153
90 Days or More Past Due and Accruing | 0 | 0
Non-Performing Loans | Substandard | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 4,984 | 6,229
Non-accrual loans | 4,837 | 6,229
90 Days or More Past Due and Accruing | 147 | 0
Non-Performing Loans | Substandard | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 479 | 1,080
Non-accrual loans | 314 | 906
90 Days or More Past Due and Accruing | 165 | 174
Non-Performing Loans | Substandard | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 281 | 191
Non-accrual loans | 281 | 191
90 Days or More Past Due and Accruing | 0 | 0
Non-Performing Loans | Substandard | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 28 | 287
Non-accrual loans | 28 | 37
90 Days or More Past Due and Accruing | 0 | 250
Non-Performing Loans | Special Mention | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 |
Non-accrual loans | 280 |
90 Days or More Past Due and Accruing | 0 |
Non-Performing Loans | Special Mention | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 85
Non-accrual loans |  | 0
90 Days or More Past Due and Accruing |  | 85
Non-Performing Loans | Pass | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 500
Non-accrual loans |  | 0
90 Days or More Past Due and Accruing |  | 500
Non-Performing Loans | Pass | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 72 | 101
Non-accrual loans | 0 | 0
90 Days or More Past Due and Accruing | 72 | 101
Non-Performing Loans | Pass | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 3
Non-accrual loans |  | 0
90 Days or More Past Due and Accruing |  | 3
Non-Performing Loans | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 2,972 | 3,302
Non-Performing Loans | Current | Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 2,944 | 3,302
Non-Performing Loans | Current | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | Current | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 2,944 | 2,829
Non-Performing Loans | Current | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 413
Non-Performing Loans | Current | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 60
Non-Performing Loans | Current | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 28 | 0
Non-Performing Loans | Current | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | Current | Substandard | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | Current | Substandard | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 2,944 | 2,829
Non-Performing Loans | Current | Substandard | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 413
Non-Performing Loans | Current | Substandard | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 60
Non-Performing Loans | Current | Substandard | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 28 | 0
Non-Performing Loans | Current | Special Mention | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 |
Non-Performing Loans | Current | Special Mention | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | Current | Pass | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | Current | Pass | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | Current | Pass | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 | 537
Non-Performing Loans | 30-89 Days Past Due | Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 | 537
Non-Performing Loans | 30-89 Days Past Due | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 | 0
Non-Performing Loans | 30-89 Days Past Due | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 537
Non-Performing Loans | 30-89 Days Past Due | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 30-89 Days Past Due | Substandard | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 | 0
Non-Performing Loans | 30-89 Days Past Due | Substandard | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 537
Non-Performing Loans | 30-89 Days Past Due | Substandard | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Substandard | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Substandard | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Special Mention | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 |
Non-Performing Loans | 30-89 Days Past Due | Special Mention | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 30-89 Days Past Due | Pass | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 30-89 Days Past Due | Pass | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 0
Non-Performing Loans | 30-89 Days Past Due | Pass | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 90 Days or More Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 4,370 | 4,677
Non-Performing Loans | 90 Days or More Past Due | Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 4,370 | 4,640
Non-Performing Loans | 90 Days or More Past Due | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 1,602 | 1,153
Non-Performing Loans | 90 Days or More Past Due | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 2,173 | 2,863
Non-Performing Loans | 90 Days or More Past Due | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 314 | 493
Non-Performing Loans | 90 Days or More Past Due | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 281 | 131
Non-Performing Loans | 90 Days or More Past Due | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 37
Non-Performing Loans | 90 Days or More Past Due | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 90 Days or More Past Due | Substandard | Real Estate | Multifamily |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 1,602 | 1,153
Non-Performing Loans | 90 Days or More Past Due | Substandard | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 1,893 | 2,863
Non-Performing Loans | 90 Days or More Past Due | Substandard | Real Estate | One-to-four family residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 314 | 493
Non-Performing Loans | 90 Days or More Past Due | Substandard | Real Estate | Home equity and lines of credit |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 281 | 131
Non-Performing Loans | 90 Days or More Past Due | Substandard | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 0 | 37
Non-Performing Loans | 90 Days or More Past Due | Special Mention | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | 280 |
Non-Performing Loans | 90 Days or More Past Due | Special Mention | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 90 Days or More Past Due | Pass | Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | 0
Non-Performing Loans | 90 Days or More Past Due | Pass | Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net | $ 0 | 0
Non-Performing Loans | 90 Days or More Past Due | Pass | Other loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans held-for-investment, net |  | $ 0

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