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

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- Definition

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

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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

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

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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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt (Schedule of debt instruments) (Details) - USD ($)	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long term debt	$ 2,680,000,000		$ 2,708,000,000
Total	$ 2,680,000,000		2,858,000,000
5.875%, face amount of $500, due August 15, 2020
Debt Instrument [Line Items]
Stated interest rate	5.875%
Face amount	$ 500,000,000
Long term debt	$ 499,000,000		498,000,000
5.750%, face amount of $400, due August 15, 2021
Debt Instrument [Line Items]
Stated interest rate	5.75%
Face amount	$ 400,000,000
Long term debt	$ 399,000,000		398,000,000
3.950%, face amount of $550, due May 15, 2024
Debt Instrument [Line Items]
Stated interest rate	3.95%
Face amount	$ 550,000,000
Long term debt	$ 547,000,000		547,000,000
4.500%, face amount of $500, due March 1, 2026
Debt Instrument [Line Items]
Stated interest rate	4.50%
Face amount	$ 500,000,000
Long term debt	$ 498,000,000		498,000,000
3.450%, face amount of $500, due August 15, 2027
Debt Instrument [Line Items]
Stated interest rate	3.45%
Face amount	$ 500,000,000
Long term debt	$ 495,000,000		495,000,000
Debenture of CNAF, 7.250%, face amount of $243, due November 15, 2023
Debt Instrument [Line Items]
Stated interest rate	7.25%
Face amount	$ 243,000,000
Long term debt	242,000,000		242,000,000
Subordinated variable rate debt of Hardy, face amount of $30, due September 15, 2036(1)
Debt Instrument [Line Items]
Face amount	30,000,000
Long term debt	$ 0		30,000,000
Debt instrument, redemption amount		$ 30,000,000
Senior notes 6.950%, face amount $150, due January 15, 2018 [Member]
Debt Instrument [Line Items]
Stated interest rate	6.95%
Face amount	$ 150,000,000
Short term debt	$ 0		$ 150,000,000