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Fair Value Measurements - Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | $ 1,086,868 | $ 1,208,237
Trading securities | 10,401 | 13,461
Individually evaluated loans | 2,902 | 3,807
Investment measured at fair value | 7,500 | 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 | 1,086,868 | 1,208,237
Trading securities | 10,401 | 13,461
Equity securities | 296 | 328
Total | 1,097,565 | 1,222,026
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 | 74,803 | 2,290
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 | 821,239 | 973,116
Measured on a recurring basis | Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 513,426 | 581,406
Measured on a recurring basis | REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 307,813 | 391,710
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 | 52 | 72
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 | 190,774 | 232,759
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 | 190,826 | 232,831
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 | 10,401 | 13,461
Equity securities | 296 | 328
Total | 10,697 | 13,789
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) | 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) | 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) | 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) | 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 | 1,086,868 | 1,208,237
Trading securities | 0 | 0
Equity securities | 0 | 0
Total | 1,086,868 | 1,208,237
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 | 74,803 | 2,290
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 | 821,239 | 973,116
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Pass-through certificates, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 513,426 | 581,406
Measured on a recurring basis | Significant Other Observable Inputs (Level 2) | REMICs, GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Debt securities available-for-sale | 307,813 | 391,710
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 | 52 | 72
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 | 190,774 | 232,759
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 | 190,826 | 232,831
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) | 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) | 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) | 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) | 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 | 2,902 | 3,907
Measured on a non-recurring basis | Real estate loans: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 2,838 | 3,795
Measured on a non-recurring basis | Real estate loans: | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 2,812 | 3,599
Measured on a non-recurring basis | Real estate loans: | Home equity and lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 26 | 27
Measured on a non-recurring basis | Real estate loans: | One-to-four family residential mortgage |  |
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 loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 64 | 12
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 loans: |  |
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 loans: | 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 loans: | 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 loans: | One-to-four family residential mortgage |  |
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 loans |  |
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 loans: |  |
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 loans: | 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 loans: | 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 loans: | One-to-four family residential mortgage |  |
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 loans |  |
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 | 2,902 | 3,907
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real estate loans: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 2,838 | 3,795
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real estate loans: | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 2,812 | 3,599
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real estate loans: | Home equity and lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | 26 | 27
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3) | Real estate loans: | One-to-four family residential mortgage |  |
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 loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Individually evaluated loans | $ 64 | 12
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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