Variable Interest Entities (Asset & Liability Balances) (Details) - USD ($) $ in Millions		Jun. 30, 2020	Dec. 31, 2019
Nonconsolidated VIEs [Member] | Investment in non-consolidated CLOs [Member]
Liabilities
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets		$ 3	$ 4
Nonconsolidated VIEs [Member] | Property funds [Member]
Liabilities
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets		11	12
Nonconsolidated VIEs [Member] | Sponsored hedge funds and private equity funds [Member]
Liabilities
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets		0	0
Nonconsolidated VIEs [Member] | Non-U.S. series funds [Member]
Liabilities
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets		21	15
Nonconsolidated VIEs [Member] | Affordable housing partnerships and other real estate partnerships[Member]
Liabilities
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets		235	270
Variable Interest Entity, Nonconsolidated, Carrying Amount, Liabilities		12	15
Variable Interest Entity, Primary Beneficiary [Member]
Liabilities
Debt	[1]	1,489	1,628
Estimated fair value of CLO debt		1,500	1,700
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Assets
Investments		1,495	1,606
Receivables		20	8
Total assets at fair value		1,515	1,614
Liabilities
Debt	[1]	1,489	1,628
Other liabilities		58	84
Total liabilities at fair value		1,547	1,712
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Corporate debt securities [Member]
Assets
Investments		10	8
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Common stocks [Member]
Assets
Investments			1
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Syndicated loans [Member]
Assets
Investments		1,485	1,597
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member]
Assets
Investments		0	1
Total assets at fair value		0	1
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | Common stocks [Member]
Assets
Investments			1
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 2 [Member]
Assets
Investments		1,284	1,462
Receivables		20	8
Total assets at fair value		1,304	1,470
Liabilities
Debt	[1]	1,489	1,628
Other liabilities		58	84
Total liabilities at fair value		1,547	1,712
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 2 [Member] | Corporate debt securities [Member]
Assets
Investments		10	8
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 2 [Member] | Syndicated loans [Member]
Assets
Investments		1,274	1,454
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 3 [Member]
Assets
Investments		211	143
Total assets at fair value		211	143
Recurring basis [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Level 3 [Member] | Syndicated loans [Member]
Assets
Investments		$ 211	$ 143

[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 $1.5 billion and $1.7 billion as of June 30, 2020 and December 31, 2019, respectively.