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Securities - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Realized gains on sales		$ 9.3	$ 11.8
Investments pledged, carrying value	$ 134.8	$ 115.0
Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Underwater security	10 years
Loss position existed	3 years

X

- Definition

For under water securities loss position expiration period.

+ References

No definition available.

+ Details

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- Definition

Maturity period for under water securities.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

No definition available.

+ Details

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X

- Definition

Amount of gain (loss) on sale or disposal of assets utilized in financial service operations.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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