Variable Annuity and Insurance Guarantees (Separate Account Balances by Type) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Mutual funds
Variable Annuity and Insurance Guarantees
Total mutual funds	$ 82,211	$ 78,931
Equity
Variable Annuity and Insurance Guarantees
Total mutual funds	48,376	45,947
Bond
Variable Annuity and Insurance Guarantees
Total mutual funds	25,684	26,073
Other
Variable Annuity and Insurance Guarantees
Total mutual funds	$ 8,151	$ 6,911

Fair value amount of the specified investment category of assets maintained in separate accounts as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 80
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121641442&loc=d3e19393-158473

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121639652&loc=d3e7104-158389

Name:	us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant