Variable Interest Entities - Additional Information (Details) $ in Millions	Sep. 30, 2021 USD ($) entity	Dec. 31, 2020 USD ($)
Investments In Variable Interest Entities [Abstract]
Number of consolidated entities | entity	3
Variable Interest Entity [Line Items]
Maximum exposure to loss in unconsolidated VIEs	$ 1,216	$ 859
Total assets	190,996	115,511
Trust preferred securities	90
Consolidated
Variable Interest Entity [Line Items]
Maximum exposure to loss in unconsolidated VIEs	777
Total assets	794	438
Unconsolidated
Variable Interest Entity [Line Items]
Total assets	$ 1,222	$ 859