Borrowings - Additional Information (Detail) $ in Millions	Dec. 31, 2022 USD ($)
Short-term Debt [Line Items]
Federal Home Loan Bank advances are secured by first and second mortgage loans and mortgage warehouse loans	$ 1,600.0
Available credit lines with various money center banks	438.0
Federal Home Loan Bank, Advances, Putable Option
Short-term Debt [Line Items]
Putable advances	$ 350.0

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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