Short-Term Borrowings - Short-Term Borrowings and the Related Weighted-Average Interest Rates (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Short-term Debt [Line Items]
Short-term borrowings	$ 128,242	$ 128,844
Federal Funds Purchased [Member]
Short-term Debt [Line Items]
Short-term borrowings	0	0
Securities Sold Under Agreements to Repurchase [Member]
Short-term Debt [Line Items]
Short-term borrowings	$ 128,242	$ 128,844

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Name:	us-gaap_ShortTermBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant