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Fair Value Measurement - Fair Value, Assets And Liabilities Measured On Recurring And Nonrecurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | $ 1,208,237 | $ 1,264,805
Trading securities | 13,461 | 12,291
Equity securities | 328 | 253
Individually evaluated loans | 3,807 | 5,325
Investment measured at fair value | 5,000 |
Measured on a recurring basis |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 1,208,237 | 1,264,805
Trading securities | 13,461 | 12,291
Equity securities | 328 | 253
Total | 1,222,026 | 1,277,349
Measured on a recurring basis | U.S. Government agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 2,290 | 3,158
Measured on a recurring basis | Mortgage-backed securities: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 973,116 | 1,172,312
Measured on a recurring basis | Mortgage-backed securities, Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 581,406 | 281,343
Measured on a recurring basis | Mortgage-backed securities, REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 391,710 | 890,965
Measured on a recurring basis | Mortgage-backed securities, REMICs, Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 4
Measured on a recurring basis | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 72 | 123
Measured on a recurring basis | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 232,759 | 88,418
Measured on a recurring basis | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 794
Measured on a recurring basis | Other debt securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 232,831 | 89,335
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Trading securities | 13,461 | 12,291
Equity securities | 328 | 253
Total | 13,789 | 12,544
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Government agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities, Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities, REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities, REMICs, Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 0
Measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other debt securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 1,208,237 | 1,264,805
Trading securities | 0 | 0
Equity securities | 0 | 0
Total | 1,208,237 | 1,264,805
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | U.S. Government agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 2,290 | 3,158
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 973,116 | 1,172,312
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities, Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 581,406 | 281,343
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities, REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 391,710 | 890,965
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities, REMICs, Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 4
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 72 | 123
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 232,759 | 88,418
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 794
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Other debt securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 232,831 | 89,335
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Trading securities | 0 | 0
Equity securities | 0 | 0
Total | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | U.S. Government agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities, Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities, REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities, REMICs, Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Municipal bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale |  | 0
Measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Other debt securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 0 | 0
Measured on a non-recurring basis |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total | 3,907 | 5,325
Measured on a non-recurring basis | Real Estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 3,795 | 5,312
Measured on a non-recurring basis | Real Estate | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 3,599 | 5,268
Measured on a non-recurring basis | Real Estate | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans |  | 16
Measured on a non-recurring basis | Real Estate | Home Equity and Lines of Credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 27 | 28
Measured on a non-recurring basis | Real Estate | One-to-Four Family |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 169 |
Measured on a non-recurring basis | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 12 | 13
Measured on a non-recurring basis | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 100 |
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total | 0 | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Real Estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Real Estate | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Real Estate | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans |  | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Real Estate | Home Equity and Lines of Credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Real Estate | One-to-Four Family |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 |
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 |
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total | 0 | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Real Estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Real Estate | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Real Estate | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans |  | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Real Estate | Home Equity and Lines of Credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Real Estate | One-to-Four Family |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 |
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 | 0
Measured on a non-recurring basis | Significant Other Observable Inputs (Level 2) | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 0 |
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total | 3,907 | 5,325
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real Estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 3,795 | 5,312
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real Estate | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 3,599 | 5,268
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real Estate | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans |  | 16
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real Estate | Home Equity and Lines of Credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 27 | 28
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real Estate | One-to-Four Family |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 169 |
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 12 | $ 13
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | $ 100 |

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