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Loans - Narrative, Net Loans Held-for-Investment (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans receivable held-for-sale, amount | $ 0 | $ 19,895
PCI loans | 3,806,617 | 3,823,238
Purchased Credit-Impaired |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
PCI loans | $ 15,819 | $ 18,518
One-to-Four Family |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Purchased credit-impaired (PCI) loan percent | 16.00% | 22.00%
Commercial real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Purchased credit-impaired (PCI) loan percent | 25.00% | 23.00%
Commercial and Industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Purchased credit-impaired (PCI) loan percent | 48.00% | 40.00%

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