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Fair Values of Assets and Liabilities (Narrative) (Detail) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Available-for-sale securities | $ 3,243,017,000 | $ 2,327,793,000 |  |
Loans held-for-investment | 179,932,000 | 38,598,000 |  |
MSRs | 230,225,000 | 147,571,000 | $ 92,081,000 | $ 85,638,000
Individually assessed loans - foreclosure probable and collateral-dependent | 90,197,000 | 93,270,000 |  |
Estimate of Fair Value Measurement |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Available-for-sale securities | 3,243,017,000 | 2,327,793,000 |  |
Remaining contractual principal balance outstanding, mortgage loans held-for-sale | 308,900,000 | 801,600,000 |  |
Remaining contractual principal balance outstanding, mortgage loans held-for-investment | 184,000,000 | 38,400,000 |  |
Non-performing |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Mortgage loans held-for-sale classified as nonaccrual | 5,800,000 |  |  |
Mortgage loans held-for-sale classified greater than 90 days past due and still accruing | $ 44,000,000 | 125,500,000 |  |
Weighted Average | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Life of loans | 5 years 9 months 18 days |  |  |
Appraisal adjustment - cost of sale | Other real estate owned |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Other real estate owned, measurement input | 0.10 |  |  |
Measured at fair value on a recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Mortgage loans held-for-sale | $ 299,935,000 | 817,912,000 |  |
Loans held-for-investment | 179,932,000 | 38,598,000 |  |
MSRs | 230,225,000 | 147,571,000 |  |
Derivative assets | 296,848,000 | 165,008,000 |  |
Measured at fair value on a non-recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | 69,019,000 |  |  |
Other real estate owned | 9,900,000 |  |  |
Level 3 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | 90,200,000 |  |  |
Level 3 | Portion at Other than Fair Value Measurement |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | 21,200,000 |  |  |
Level 3 | Measured at fair value on a recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Mortgage loans held-for-sale | 48,655,000 | 0 |  |
Loans held-for-investment | 84,165,000 | 15,891,000 |  |
MSRs | 230,225,000 | 147,571,000 |  |
Derivative assets | $ 1,711,000 | 10,560,000 |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Weighted Average | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 0.1030 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Weighted Average | Mortgage loans held-for-sale |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0621 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Weighted Average | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0626 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Weighted Average | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.1030 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Minimum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 0.07 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Minimum | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.07 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Maximum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 0.24 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Discount rate | Maximum | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.24 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Weighted Average | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 0.0662 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Weighted Average | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0662 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Weighted Average | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0662 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Minimum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 0 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Minimum | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Maximum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 1 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) | Maximum | Mortgage Servicing Rights |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 1 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Weighted Average | Mortgage loans held-for-sale |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0033 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Weighted Average | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.0077 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Minimum | Mortgage loans held-for-sale |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Minimum | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Maximum | Mortgage loans held-for-sale |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.12 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Credit discount | Maximum | Loans held-for-investment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Discount rate | 0.12 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing | Weighted Average | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 75 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing | Minimum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 70 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing | Maximum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 200 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Weighted Average | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | 343 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Minimum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 200 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Maximum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
MSRs, measurement input | $ / shares | 1,000 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Pull-through rate | Weighted Average | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, measurement input | 0.8612 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Pull-through rate | Minimum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, measurement input | 0.35 |  |  |
Level 3 | Measured at fair value on a recurring basis: | Pull-through rate | Maximum | Discounted cash flows |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Derivatives, measurement input | 1 |  |  |
Level 3 | Measured at fair value on a non-recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Individually assessed loans - foreclosure probable and collateral-dependent | $ 69,019,000 |  |  |
Other real estate owned | 9,900,000 |  |  |
Municipal securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Available-for-sale securities | 168,655,000 | 165,594,000 |  |
Municipal securities | Measured at fair value on a recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Available-for-sale securities | 168,655,000 | 165,594,000 |  |
Municipal securities | Level 3 | Measured at fair value on a recurring basis: |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Available-for-sale securities | $ 117,537,000 | $ 105,687,000 |  |

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- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
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