Separate Accounts - Separate Account Assets (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	$ 107,278	$ 101,676
U.S. Government agencies and authorities
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	979	913
Corporate and foreign debt securities
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	2,544	2,493
Mortgage-backed securities
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	3,134	3,087
Equity securities (including mutual funds)
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	99,693	94,685
Cash, cash equivalents and short-term investments
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	522	437
Receivable for securities and accruals
Fair Value, Separate Account Investment [Line Items]
Assets held in separate accounts	$ 406	$ 61

Amount of asset at fair value held for benefit of separate account policyholder.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480078/944-80-55-17

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480078/944-80-55-14

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480078/944-80-55-9

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480109/944-80-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480141/944-80-45-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(11))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480141/944-80-45-2

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