Lending Activities - Loan Modifications (Details) - Extended Maturity - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2023
Commercial Mortgage Loans
Allowance for losses on Mortgage and other loans receivable
Amortized cost	$ 51	$ 51
Commercial Loans, Other Loans, And Notes Receivable
Allowance for losses on Mortgage and other loans receivable
Amortized cost	$ 168	$ 168

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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