Debt (New Subordinated Debt Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2022 USD ($)
Debt Disclosure [Abstract]
Debt Instrument, Issuance Date	Sep. 23, 2022
Debt Instrument, Interest Rate, Stated Percentage	7.125%
Debt Instrument, Face Amount	$ 700
Proceeds from Debt, Net of Issuance Costs	690
Debt Issuance Costs, Net	$ 10
Debt Instrument, Description	On September 23, 2022, RGA issued 7.125% fixed-rate reset subordinated debentures due October 15, 2052, with a face amount of $700 million. This security has been registered with the Securities and Exchange Commission. The net proceeds were approximately $690 million and a portion was used in part to pay for the tender offer of the 2042 Debentures. The remaining proceeds will be used for future redemptions of any remaining 2042 Debentures, and general corporate purposes. Capitalized issue costs were approximately $10 million.

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Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date the debt instrument was issued, in YYYY-MM-DD format.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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