Deposits - Narrative (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Deposit Liability [Line Items]
Time deposits greater than $250,000	$ 160.4	$ 85.5
Demand deposit overdrafts reclassified as loans	4.1	$ 3.7
State and municipal deposits	591.3
Asset Pledged as Collateral
Deposit Liability [Line Items]
Available borrowing capacity through FHLB	$ 599.4

Deposits, State And Municipal, Secured By Collateral

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- Definition

Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

+ References

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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481047/942-405-50-1

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Industry Guide
-Number 3
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-Paragraph D-E
-Publisher SEC

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

+ References

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