Loans and Allowance for Credit Losses - Activity in the Allowance for Credit Losses for Loans Held for Investment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			$ 122
Provision	$ (2)
Ending balance	95		95
Leveraged Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	74	$ 113	97	$ 61
Charge-offs	(1)	(14)	(2)	(33)
Provision	(4)	3	(24)	73
Other	(1)		(3)
Foreign currency translation		4		5
Ending balance	68	106	68	106
Other Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	12	20	17	10
Charge-offs	0	0	0	0
Provision	0	0	(5)	10
Other	0		0
Foreign currency translation		0		0
Ending balance	12	20	12	20
Other Loans | Fund Finance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Ending balance	11	15	11	15
Other Loans | Other Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Ending balance	1	5	1	5
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	14	8	8	2
Charge-offs	0	0	0	0
Provision	1	0	7	6
Other	0		0
Foreign currency translation		0		0
Ending balance	15	8	15	8
Held-to-Maturity Securities
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2	3	3	0
Charge-offs	0	0	0	0
Provision	0	0	(1)	3
Other	0		0
Foreign currency translation		0		0
Ending balance	2	3	2	3
Off-Balance Sheet Commitments
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	19	18	22	19
Charge-offs	0	0	0	0
Provision	1	(3)	(2)	(4)
Other	0		0
Foreign currency translation		0		0
Ending balance	20	15	20	15
All Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	1	1	1
Charge-offs	0	0	0	0
Provision	0	0	(1)	0
Other	0		0
Foreign currency translation		0		0
Ending balance	0	1	0	1
Total
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	121	163	148	93
Charge-offs	(1)	(14)	(2)	(33)
Provision	(2)	0	(26)	88
Other	(1)		(3)
Foreign currency translation		4		5
Ending balance	$ 117	$ 153	$ 117	$ 153