Asset Management Fees - Asset Management Fees (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Asset management fees	$ 53	$ 93	$ 88
Asset management fees
Disaggregation of Revenue [Line Items]
Asset management fees	21	53	65
Performance fees
Disaggregation of Revenue [Line Items]
Asset management fees	18	19	1
Reimbursable fund expenses
Disaggregation of Revenue [Line Items]
Asset management fees	$ 14	$ 21	$ 22