Variable Interest Entities - Variable Interests Held by Us and Our Maximum Exposure to Loss Rising From Our Involvements in Those VIEs (Details) - USD ($) $ in Millions		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Variable Interest Entity [Line Items]
Assets		$ 196,434	[1]	$ 175,375	[1]	$ 172,448
Liabilities	[1]	178,143		157,119
Structured Note Vehicles [Member]
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs				1,524
Assets				510
Liabilities				9
Maximum Exposure to Loss				1,515
Limited Partnership Investments [Member]
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs		4,266		2,160
Assets		629		561
Liabilities		285		300
Maximum Exposure to Loss		$ 629		562
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs				3,684
Assets				1,071
Liabilities				309
Maximum Exposure to Loss				$ 2,077

[1] Assets