Borrowings - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Short-term Debt [Line Items]
Federal Home Loan Bank advances are secured by first and second mortgage loans and mortgage warehouse loans	$ 1,000
Available credit lines with various money center banks	$ 1,000
Maximum
Short-term Debt [Line Items]
Call date	Oct. 24, 2022
Minimum
Short-term Debt [Line Items]
Call date	Feb. 01, 2021
Federal Home Loan Bank, Advances, Putable Option
Short-term Debt [Line Items]
Putable advances	$ 200

Federal Home Loan Bank Borrowings Call Date.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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-Name Accounting Standards Codification
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-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
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-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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-Topic 210
-SubTopic 10
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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ References

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