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Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
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Mortgage Loans Held For Sale |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Notional amount | $ 355.0 | $ 378.1
IRLCs |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Notional amount | $ 479.3 | $ 652.1

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