Investments - Investments - Past-Due Mortgage Loans (Details) - Commercial Loan [Member] - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 6,245	$ 6,138
Financial Asset, Past Due
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 0	$ 0

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details