Loans and Leases Held for Investment at Amortized Cost, Net of Allowance For Loan and Lease Losses - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Term Loans and Leases by Origination Year
Accrued interest receivable, location	Other assets	Other assets
Accrued interest	$ 32.2	$ 27.9
Combination – Interest Payment Reduction and Term Extension
Term Loans and Leases by Origination Year
Combination and settlement loan modification	0.5
Debt Settlement
Term Loans and Leases by Origination Year
Combination and settlement loan modification	$ 53.1