Variable Interest Entities - Narrative (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Unconsolidated tax credit structures investments, location	Other Assets	Other Assets
Income tax credits and other income tax benefits associated with tax credit investments, statements of cash flows location not disclosed	Income tax credits and other income tax benefits	Income tax credits and other income tax benefits	Income tax credits and other income tax benefits
Amortization expense, statements of cash flows location not disclosed	amortization expense	amortization expense	amortization expense
Income tax credits and other income tax benefits associated with tax credit investments, statements of income location	Provision for Income Taxes	Provision for Income Taxes	Provision for Income Taxes
Amortization associated with unconsolidated tax credit investments, statements of income location	Provision for Income Taxes	Other Operating Expense	Other Operating Expense
Investment company, financial support to investee contractually required, amount	$ 0