Fair Value Disclosures - Investments in Certain Entities Calculate Net Asset Value per Share (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total Unfunded Commitments	$ 740	$ 725
Real Assets Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total Unfunded Commitments	268	272
Total remaining Unfunded Commitments	$ 241	$ 248