Asset Management Fees - Asset Management Fees (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Asset management fees	$ 17	$ 0	$ 60	$ 0
CLOs
Disaggregation of Revenue [Line Items]
Asset management fees	4		11
Opportunity funds and liquid strategies
Disaggregation of Revenue [Line Items]
Asset management fees	1		5
Wind-down funds
Disaggregation of Revenue [Line Items]
Asset management fees	6		21
Asset management fees
Disaggregation of Revenue [Line Items]
Asset management fees	11		37
Reimbursable fund expenses
Disaggregation of Revenue [Line Items]
Asset management fees	6		23
CLO's, Before Rebates
Disaggregation of Revenue [Line Items]
Asset management fees	$ 7		$ 24