Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Other	$ (19)	$ (18)
Long-term debt	4,231	4,232
Less: amount due within one year	3	5
Total long-term debt	$ 4,228	4,227
5.125% Notes, due 2024
Debt Instrument [Line Items]
Long-term debt, interest rate	5.125%
Amount outstanding	$ 1,150	1,150
6.875% Notes, due 2025
Debt Instrument [Line Items]
Long-term debt, interest rate	6.875%
Amount outstanding	$ 600	600
5.900% Notes, due 2027
Debt Instrument [Line Items]
Long-term debt, interest rate	5.90%
Amount outstanding	$ 625	625
6.750% Bonds, due 2028
Debt Instrument [Line Items]
Long-term debt, interest rate	6.75%
Amount outstanding	$ 300	300
3.000% Notes, due 2029
Debt Instrument [Line Items]
Long-term debt, interest rate	3.00%
Amount outstanding	$ 700	700
5.950% Notes, due 2037
Debt Instrument [Line Items]
Long-term debt, interest rate	5.95%
Amount outstanding	$ 625	625
4.750% Iowa Finance Authority Loan, due 2042
Debt Instrument [Line Items]
Long-term debt, interest rate	4.75%
Amount outstanding	$ 250	$ 250

Other Long Term Debt, Including Unamortized Debt Discounts And Issuance Costs

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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