Variable Interest Entities (Changes in Level 3 Assets and Liabilities) (Details 2) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019
Syndicated loans [Member]
Summary of changes in Level 3 assets measured at fair value on a recurring basis [Rollforward]
Balance, at the beginning of the period		$ 211		$ 130	$ 143		$ 226
Total gains (losses) included in net income		2	[1]	0	(19)	[1]	(1)	[1]
Purchases		35		26	80		75
Sales		(12)			(27)		(8)
Settlements		(6)		(25)	(32)		(36)
Transfers into Level 3		29		81	379		165
Transfers out of Level 3		(141)		(77)	(406)		(286)
Balance, at the end of the period		118		135	118		135
Changes in unrealized gains (losses) included in income relating to assets held at end of period	[1]	$ 1		(1)	$ (2)		(2)
Common stocks [Member]
Summary of changes in Level 3 assets measured at fair value on a recurring basis [Rollforward]
Balance, at the beginning of the period				1			0
Transfers into Level 3							1
Transfers out of Level 3				(1)			(1)
Balance, at the end of the period				$ 0			$ 0

[1] Included in net investment income in the Consolidated Statements of Operations.