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Restrictions of Dividends & Inter-company Borrowings - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Dividends may be paid without prior regulatory approval	$ 47.4
Perpetual Federal Savings Bank [Member]
Class of Stock [Line Items]
Dividend approved by federal reserve for the acquisition		$ 40.0

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