Long-Term Debt - Subordinated Debt (Details) - Parent Company - Subordinated Debt - USD ($)		12 Months Ended
Nov. 20, 2013	Dec. 31, 2021
Fixed Rate 8.25% Notes Due 2038
Debt Instrument
Issue of senior notes to third party investors		$ 1,000,000,000
Interest rate (as a percent)		8.25%
Amount of debt converted to floating rate		$ 705,000,000
Interest rate paid (as a percent)		3.22%
Fixed Rate 8.25% Notes Due 2038 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)		3.05%
Fixed Rate 4.30% Notes Due 2024
Debt Instrument
Interest rate (as a percent)	4.30%	4.30%
Principal amount	$ 750,000,000
Redemption period prior to maturity date	30 days
Redemption price (as a percent)	100.00%

Debt Instrument, Redemption Period Prior To Maturity Date

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- Definition

Notional amount of floating interest rate debt with interest rate hedge.

+ References

No definition available.

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- Definition

Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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