Short-Term and Long-Term Debt (Schedule Of Debt) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Short-term debt	$ 1,084	$ 497
Total long-term debt	$ 2,334	2,412
9.76% Surplus Note, Due 2024 [Member]
Debt Instrument [Line Items]
Stated interest rate	9.76%
9.76% Surplus Note, Due 2024 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 50	50
Stated interest rate	9.76%
6.56% Surplus Note, Due 2028 [Member]
Debt Instrument [Line Items]
Stated interest rate	6.56%
6.56% Surplus Note, Due 2028 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 500	500
Stated interest rate	6.56%
111 bps Surplus Note, Due 2028 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.11%
111 bps Surplus Note, Due 2028 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 71	71
111 bps Surplus Note, Due 2028 [Member] \| Long-term Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.11%
226 bps Surplus Note, Due 2028 [Member]
Debt Instrument [Line Items]
Surplus notes	$ 593
226 bps Surplus Note, Due 2028 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.26%
226 bps Surplus Note, Due 2028 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 593	611
226 bps Surplus Note, Due 2028 [Member] \| Long-term Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.26%
6.03% Surplus Note, Due 2028 [Member]
Debt Instrument [Line Items]
Stated interest rate	6.03%
6.03% Surplus Note, Due 2028 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 750	750
Stated interest rate	6.03%
200 bps Surplus Note, Due 2035 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.00%
200 bps Surplus Note, Due 2035 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 30	30
200 bps Surplus Note, Due 2035 [Member] \| Long-term Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.00%
155 bps Surplus Note, Due 2037 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.55%
155 bps Surplus Note, Due 2037 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 25	25
155 bps Surplus Note, Due 2037 [Member] \| Long-term Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.55%
4.20% Surplus Note, Due 2037 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.20%
4.20% Surplus Note, Due 2037 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 50	50
Stated interest rate	4.20%
100 bps Surplus Note, Due 2037 [Member]
Debt Instrument [Line Items]
Surplus notes	$ 194
100 bps Surplus Note, Due 2037 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.00%
100 bps Surplus Note, Due 2037 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 194	254
100 bps Surplus Note, Due 2037 [Member] \| Long-term Debt [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.00%
4.225% Surplus Notes, Due 2037 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.225%
4.225% Surplus Notes, Due 2037 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 28	28
Stated interest rate	4.225%
4.00% Surplus Notes, Due 2037 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.00%
4.00% Surplus Notes, Due 2037 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 30	30
Stated interest rate	4.00%
4.50% Surplus Note, Due 2038 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.50%
4.50% Surplus Note, Due 2038 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Surplus notes	$ 13	$ 13
Stated interest rate	4.50%

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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