Fair Value (Carrying amount and estimated fair value of financial instrument assets and liabilities which are not measured at fair value) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Assets
Mortgage loans	$ 1,079	$ 1,019
Liabilities
Long-term debt	2,971	2,973
Carrying Amount
Assets
Mortgage loans	1,079	1,019
Liabilities
Long-term debt	2,971	2,973
Estimated Fair Value
Assets
Mortgage loans	1,072	987
Liabilities
Long-term debt	2,967	2,885
Level 1 \| Estimated Fair Value
Assets
Mortgage loans	0	0
Liabilities
Long-term debt	0	0
Level 2 \| Estimated Fair Value
Assets
Mortgage loans	0	0
Liabilities
Long-term debt	2,967	2,885
Level 3 \| Estimated Fair Value
Assets
Mortgage loans	1,072	987
Liabilities
Long-term debt	$ 0	$ 0

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

Reference 1: 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 2: 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 3: 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)(1)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 4: 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)(1)(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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