Offsetting Assets and Liabilities - Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2021	Dec. 31, 2020
Derivatives:
Gross Amounts of Recognized Liabilities		$ 4,114	$ 4,312
Amounts of Liabilities Presented in the Consolidated Balance Sheets		4,114	4,312
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(3,604)	(3,978)
Cash Collateral		(195)	(1)
Securities Collateral		(293)	(327)
Net Amount		22	6
Securities loaned
Gross Amounts of Recognized Liabilities		111	205
Amounts of Liabilities Presented in the Consolidated Balance Sheets		111	205
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(16)	(43)
Securities Collateral		(91)	(157)
Net Amount		4	5
Total
Gross Amounts of Recognized Liabilities		4,225	4,517
Amounts of Liabilities Presented in the Consolidated Balance Sheets		4,225	4,517
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(3,620)	(4,021)
Cash Collateral		(195)	(1)
Securities Collateral		(384)	(484)
Net Amount		26	11
OTC
Derivatives:
Gross Amounts of Recognized Liabilities		3,987	4,192
Amounts of Liabilities Presented in the Consolidated Balance Sheets		3,987	4,192
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(3,479)	(3,862)
Cash Collateral		(195)	(1)
Securities Collateral		(293)	(327)
Net Amount		20	2
OTC cleared
Derivatives:
Gross Amounts of Recognized Liabilities		15	25
Amounts of Liabilities Presented in the Consolidated Balance Sheets		15	25
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(15)	(25)
Exchange-traded
Derivatives:
Gross Amounts of Recognized Liabilities		112	95
Amounts of Liabilities Presented in the Consolidated Balance Sheets		112	95
Gross Amounts Not Offset in the Consolidated Balance Sheets
Financial Instruments	[1]	(110)	(91)
Net Amount		$ 2	$ 4

[1] Represents the amount of liabilities that could be offset by assets with the same counterparty under master netting or similar arrangements that management elects not to offset on the Consolidated Balance Sheets.