Variable Interest Entities - Narrative (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Investment company, voluntary fee waived	$ 8,800,000	$ 64,200,000
Investment company, financial support to investee contractually required, amount	0
Unfunded commitments	0	0
Fair value, investments, entities that calculate net asset value per share, seed capital investments		19,900,000
Tax Credit Structures
Variable Interest Entity [Line Items]
Affordable housing tax credits and other tax benefits	$ 113,900,000	$ 99,100,000