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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions			2 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2025	Oct. 10, 2025	Oct. 31, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Oct. 28, 2025	Oct. 16, 2025	Oct. 08, 2025	Oct. 07, 2025
Subsequent Event [Line Items]
Stock repurchased and retired (in shares)				844,426	3,972	952,074	49,420
Stock Repurchased and Retired During Period, Value				$ 27.5	$ 0.1	$ 30.7	$ 1.2
Subsequent Event
Subsequent Event [Line Items]
Common Stock Held in Assets										$ 0.2	$ 0.2
Deposits - branch sale		$ 645.0							$ 280.0
Loans - branch sale		305.0							$ 70.0
Sale and Leaseback Transaction, Gain (Loss), Net		$ 60.0
Stock Repurchased and Retired During Period, Value			$ 60.2
Subsequent Event | Junior Subordinated Deferrable Interest Debentures Issued by HFFC III
Subsequent Event [Line Items]
Subordinated Debt											5.0
Subsequent Event | Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV
Subsequent Event [Line Items]
Subordinated Debt										7.0
Subsequent Event | Junior Subordinated Deferrable Interest Debentures Issued by HFFC III | Junior Subordinated Deferrable Interest Debentures Issued by HFFC III
Subsequent Event [Line Items]
Subordinated Debt											$ 5.2
Subsequent Event | Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV | Junior Subordinated Deferrable Interest Debentures Issued by HFFC IV
Subsequent Event [Line Items]
Subordinated Debt										$ 7.2
Class A Common Stock
Subsequent Event [Line Items]
Stock repurchased and retired (in shares)						842,903
Class A Common Stock | Subsequent Event
Subsequent Event [Line Items]
Dividend amount per share (in dollars)								$ 0.47
Stock repurchased and retired (in shares)	1,100,000		1,900,000

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