Variable Interest Entities - Asset and Liability Balances (Details 2) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Millions		Mar. 31, 2021	Dec. 31, 2020
Liabilities
Debt Instrument, Fair Value Disclosure	[1]	$ 2,671	$ 1,913
Estimated fair value of CLO debt		2,700	2,000
Recurring basis [Member]
Assets
Investments		2,642	1,918
Receivables		17	16
Other assets		2	2
Total assets at fair value		2,661	1,936
Liabilities
Debt Instrument, Fair Value Disclosure	[1]	2,671	1,913
Other liabilities		256	69
Total liabilities at fair value		2,927	1,982
Recurring basis [Member] | Corporate debt securities [Member]
Assets
Investments			8
Recurring basis [Member] | Common stocks [Member]
Assets
Investments		2	1
Recurring basis [Member] | Syndicated loans [Member]
Assets
Investments		2,640	1,909
Recurring basis [Member] | Level 2 [Member]
Assets
Investments		2,487	1,826
Receivables		17	16
Other assets		2
Total assets at fair value		2,506	1,842
Liabilities
Debt Instrument, Fair Value Disclosure	[1]	2,671	1,913
Other liabilities		256	69
Total liabilities at fair value		2,927	1,982
Recurring basis [Member] | Level 2 [Member] | Corporate debt securities [Member]
Assets
Investments			8
Recurring basis [Member] | Level 2 [Member] | Common stocks [Member]
Assets
Investments		2	1
Recurring basis [Member] | Level 2 [Member] | Syndicated loans [Member]
Assets
Investments		2,485	1,817
Recurring basis [Member] | Level 3 [Member]
Assets
Investments		155	92
Other assets			2
Total assets at fair value		155	94
Recurring basis [Member] | Level 3 [Member] | Syndicated loans [Member]
Assets
Investments		$ 155	$ 92

[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 $2.7 billion and $2.0 billion as of March 31, 2021 and December 31, 2020, respectively.