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Loans - Investment of Originated Loans Held-for-Investment by Loan Type and Credit Quality Indicator (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | $ 3,806,617 | $ 3,823,238
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 3,790,798 | 3,804,720
Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 3,647,778 | 3,610,210
Commercial and Industrial | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 141,005 | 191,481
Other loans | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 2,015 | 3,029
Pass | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 3,731,891
Pass | Commercial and Industrial | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 133,873 | 189,372
Pass | Other loans | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 2,015 | 3,026
Special Mention | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 24,145
Special Mention | Commercial and Industrial | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 572 | 498
Special Mention | Other loans | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 0
Substandard | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 48,684
Substandard | Commercial and Industrial | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 6,560 | 1,611
Substandard | Other loans | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 3
Multifamily | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 2,518,065 | 2,512,934
Multifamily | Pass | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 2,502,531 | 2,497,556
Multifamily | Special Mention | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 425 | 458
Multifamily | Substandard | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 15,109 | 14,920
Commercial | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 808,597 | 717,566
Commercial | Pass | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 765,448 | 667,568
Commercial | Special Mention | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 10,159 | 20,422
Commercial | Substandard | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 32,990 | 29,576
One-to-Four Family | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 183,665 | 212,222
One-to-Four Family | Pass | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 177,607 | 207,633
One-to-Four Family | Special Mention | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 2,803 | 2,456
One-to-Four Family | Substandard | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 3,255 | 2,133
Home Equity and Lines of Credit | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 109,956 | 93,137
Home Equity and Lines of Credit | Pass | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 109,319 | 92,385
Home Equity and Lines of Credit | Special Mention | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 103 | 311
Home Equity and Lines of Credit | Substandard | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 534 | 441
Construction and Land | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | 27,495 | 74,351
Construction and Land | Pass | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net | $ 27,495 | 74,351
Construction and Land | Special Mention | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | 0
Construction and Land | Substandard | Real Estate | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total loans held-for-investment, net |  | $ 0

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