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Loans - Narrative, Net Loans Held-for-Investment (Details) - USD ($) $ in Thousands	12 Months Ended
	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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Percentage of Purchase Credit Impaired Loans.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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