Asset Management Fees - Asset Management Fees (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Asset management fees	$ 20	$ 17	$ 65	$ 60
CLOs
Disaggregation of Revenue [Line Items]
Asset management fees	9	4	31	11
Opportunity funds and liquid strategies
Disaggregation of Revenue [Line Items]
Asset management fees	4	1	12	5
Wind-down funds
Disaggregation of Revenue [Line Items]
Asset management fees	2	6	6	21
Asset management fees
Disaggregation of Revenue [Line Items]
Asset management fees	15	11	49	37
Performance fees
Disaggregation of Revenue [Line Items]
Asset management fees	0	0	1	0
Reimbursable fund expenses
Disaggregation of Revenue [Line Items]
Asset management fees	5	6	15	23
CLO's, Before Rebates
Disaggregation of Revenue [Line Items]
Asset management fees	$ 11	$ 7	$ 36	$ 24