Variable Interest Entities (FV Options for consolidated CDOs) (Details 3) - Consolidated investment entities [Member] - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Fair value and unpaid principal balance of assets and liabilities carried at fair value under the fair value option
Estimated fair value of CLO debt		$ 1,400		$ 1,400		$ 2,200
Syndicated loans [Abstract]
Unpaid principal balance		1,298		1,298		2,140
Excess unpaid principal over fair value		(24)		(24)		(71)
Fair value		1,274		1,274		2,069
Fair value of loans more than 90 days past due		7		7		24
Fair value of loans in nonaccrual status		7		7		24
Difference between fair value and unpaid principal of loans more than 90 days past due, loans in nonaccrual status or both		5		5		35
Debt [Abstract]
Unpaid principal balance		1,557		1,557		2,340
Excess unpaid principal over fair value		(141)		(141)		(134)
Carrying value	[1]	1,416		1,416		$ 2,206
Net investment income [Member]
Fair value and unpaid principal balance of assets and liabilities carried at fair value under the fair value option
Total net gains (losses) recognized in net investment income related to changes in the fair value of financial assets and liabilities for which the fair value option was elected		$ 25	$ 1	$ 24	$ (2)

[1] The carrying value of the CLOs’ debt is set equal to the fair value of the CLOs’ assets. The estimated fair value of the CLOs’ debt was $1.4 billion and $2.2 billion as of June 30, 2018 and December 31, 2017, respectively.