Long-Term Debt - Subordinated Debt (Details) - USD ($)	Nov. 20, 2013	Dec. 31, 2020
Debt Instrument
Principal amount		$ 1,370,000,000
Parent Company \| Subordinated Debt \| Fixed Rate 8.25% Notes Due 2038
Debt Instrument
Issue of senior notes to third party investors		$ 1,000,000,000.0
Interest rate		8.25%
Amount of debt converted to floating rate		$ 705,000,000
Parent Company \| Subordinated Debt \| Fixed Rate 8.25% Notes Due 2038 \| LIBOR
Debt Instrument
Interest rate paid		3.27%
Parent Company \| Subordinated Debt \| Fixed Rate 4.30% Notes Due 2024
Debt Instrument
Interest rate	4.30%	4.30%
Principal amount	$ 750,000,000
Redemption period prior to maturity date	30 days
Redemption price percentage	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.

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

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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.

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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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