Borrowings - Short-term Borrowings (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Total short-term debt	$ 0	$ 300,000
FHLB advances
Short-term Debt [Line Items]
Total short-term debt	$ 0	$ 300,000
FHLB advances, rate	0.00%	4.54%

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