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Debt - Schedule of Long-Term Debt (Details) € in Millions, ¥ in Millions, $ in Millions	Sep. 30, 2025 USD ($)	Sep. 30, 2025 EUR (€)	Sep. 30, 2025 JPY (¥)	Dec. 31, 2024 USD ($)	Dec. 31, 2024 JPY (¥)
Debt Instrument [Line Items]
Other, net	$ (11)			$ (13)
Long-term debt	3,189			3,315
Less: long-term debt due within one year	1			6
Total long-term debt	$ 3,188			3,309
Currency Swap
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	3.72%	3.72%	3.72%
Derivative liability | €		€ 458
USD Term Loan Facility
Debt Instrument [Line Items]
Amount outstanding	$ 0			140
USD Term Loan Facility | Unsecured Debt
Debt Instrument [Line Items]
Amount outstanding	0			$ 140
Fixed interest rate (as a percent)				5.67%	5.67%
JPY Term Loan Facility
Debt Instrument [Line Items]
Amount outstanding	200			$ 188
JPY Term Loan Facility | Unsecured Debt
Debt Instrument [Line Items]
Amount outstanding	$ 200		¥ 29,702	$ 188	¥ 29,702
Fixed interest rate (as a percent)	1.794%	1.794%	1.794%	1.919%	1.919%
5.900% Notes, due 2027
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	5.90%	5.90%	5.90%
Amount outstanding	$ 625			$ 625
6.750% Bonds, due 2028
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	6.75%	6.75%	6.75%
Amount outstanding	$ 300			300
3.000% Notes, due 2029
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	3.00%	3.00%	3.00%
Amount outstanding	$ 700			700
4.850% Notes, due 2031
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	4.85%	4.85%	4.85%
Amount outstanding	$ 500			500
5.950% Notes, due 2037
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	5.95%	5.95%	5.95%
Amount outstanding	$ 625			625
4.750% Iowa Finance Authority Loan, due 2042
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)	4.75%	4.75%	4.75%
Amount outstanding	$ 250			$ 250

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

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

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