Reserve for Future Policy Benefits and Contractholder Funds - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Reserve for Future Policy Benefits and Contractholder Funds [Abstract]
Increase (less than) in future policy benefit reserves	$ 1	$ 1

The change in the future policy benefit reserve balance on the balance sheet.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Name:	us-gaap_IncreaseDecreaseInFuturePolicyBenefitReserves
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration