Goodwill and Other Intangible Assets - Additional Information (Detail)	Jul. 06, 2018 USD ($)
FNBB [Member]
Finite-Lived Intangible Assets [Line Items]
Additions to core deposit intangibles	$ 27,605,000

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.

No definition available.

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Balance Type:	na
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