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Debt (Schedule of Debt) (Details) ¥ in Millions, SFr in Millions, $ in Millions	Mar. 31, 2026 USD ($)	Mar. 31, 2026 CNY (¥)	Mar. 31, 2026 CHF (SFr)	Dec. 31, 2025	Sep. 30, 2025	Aug. 18, 2025	Mar. 31, 2025 USD ($)	Mar. 31, 2025 CNY (¥)	Mar. 31, 2025 CHF (SFr)	Jan. 31, 2025	Aug. 31, 2021
Debt Instrument [Line Items]
Short-term borrowings	$ 1,305						$ 348
Long-term debt, principal	6,619						5,832
Total debt, carrying value	7,978						6,212
Current portion of long-term debt	54						32
Unamortized Carrying Value Adjustments, total debt	68						59
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0						0
Long-term debt, carrying value	6,572						5,790
Debt and Lease Obligation	7,910						6,153
Carrying Value, Long-term debt, net of current portion	$ 6,551						5,773
Bank Loans, Due Through August 2027
Debt Instrument [Line Items]
Interest rate	2.65%	2.65%	2.65%
Long-term debt, principal	$ 29						41	¥ 300
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 29						41
China Loan, Due September 2027
Debt Instrument [Line Items]
Interest rates					0.55%
Interest rate	2.45%	2.45%	2.45%
Long-term debt, principal	$ 14	¥ 100					13	100
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 14						13
China Loan, due November 2027
Debt Instrument [Line Items]
Interest rates				0.40%
Interest rate	2.60%	2.60%	2.60%
Long-term debt, principal	$ 22	¥ 149					21	150
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 22						21
China Loan, due December 2027
Debt Instrument [Line Items]
Interest rates				0.50%
Interest rate	2.50%	2.50%	2.50%
Long-term debt, principal	$ 22	¥ 149					21	¥ 150
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 22						21
China Loan, due January 2029
Debt Instrument [Line Items]
Interest rates	0.60%	0.60%	0.60%
Interest rate	2.40%	2.40%	2.40%
Long-term debt, principal	$ 26	¥ 180					0
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 26						0
Sierre Loan, due October 2027
Debt Instrument [Line Items]
Interest rates				0.50%
Interest rate	0.43%	0.43%	0.43%
Long-term debt, principal	$ 125		SFr 100				113		SFr 100
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 125						113
Other Debt, due through December 2020
Debt Instrument [Line Items]
Interest rate	4.73%	4.73%	4.73%
Long-term debt, principal	$ 33						15
Unamortized Carrying Value Adjustments	0						0
Long-term debt, carrying value	$ 33						15
Series 2025A Bonds, due June 2032
Debt Instrument [Line Items]
Interest rate	5.00%	5.00%	5.00%
Long-term debt, principal	$ 400						0
Unamortized Carrying Value Adjustments	5						0
Long-term debt, carrying value	$ 395						0
Series 2025 B Bonds, due June 2032
Debt Instrument [Line Items]
Interest rate	4.625%	4.625%	4.625%
Long-term debt, principal	$ 100						0
Unamortized Carrying Value Adjustments	2						0
Long-term debt, carrying value	$ 98						0
Series 2026A Bonds, due June 2033
Debt Instrument [Line Items]
Interest rate	4.30%	4.30%	4.30%
Long-term debt, principal	$ 225						0
Unamortized Carrying Value Adjustments	4						0
Long-term debt, carrying value	$ 221						0
Secured Debt \| Floating rate Term Loans, due March 2032
Debt Instrument [Line Items]
Interest rate	5.45%	5.45%	5.45%
Long-term debt, principal	$ 1,238						1,250
Unamortized Carrying Value Adjustments	14						16
Long-term debt, carrying value	$ 1,224						1,234
Senior Notes
Debt Instrument [Line Items]
Interest rate	4.75%	4.75%	4.75%
Senior Notes \| 3.250% Senior Notes, due November 2026
Debt Instrument [Line Items]
Interest rate											3.25%
Long-term debt, principal	$ 13						750
Unamortized Carrying Value Adjustments	0						3
Long-term debt, carrying value	$ 13						747
Senior Notes \| 3.375% Senior Notes, due April 2029
Debt Instrument [Line Items]
Interest rate	3.375%	3.375%	3.375%
Long-term debt, principal	$ 576						540
Unamortized Carrying Value Adjustments	5						7
Long-term debt, carrying value	$ 571						533
Senior Notes \| 4.750% Senior Notes, due January 2030
Debt Instrument [Line Items]
Interest rate	4.75%	4.75%	4.75%
Long-term debt, principal	$ 1,600						1,600
Unamortized Carrying Value Adjustments	12						15
Long-term debt, carrying value	$ 1,588						1,585
Senior Notes \| 6.875% Senior Notes, due January 2030
Debt Instrument [Line Items]
Interest rates	6.875%	6.875%	6.875%							6.875%
Interest rate	6.875%	6.875%	6.875%
Long-term debt, principal	$ 750						750
Unamortized Carrying Value Adjustments	9						11
Long-term debt, carrying value	$ 741						739
Senior Notes \| 3.875% Senior Notes, due August 2031
Debt Instrument [Line Items]
Interest rate	3.875%	3.875%	3.875%
Long-term debt, principal	$ 750						750
Unamortized Carrying Value Adjustments	6						7
Long-term debt, carrying value	744						743
Senior Notes \| 6.375% Senior Notes due August 2033
Debt Instrument [Line Items]
Interest rate						6.375%
Long-term debt, principal	750						0
Unamortized Carrying Value Adjustments	11						0
Long-term debt, carrying value	$ 739						$ 0
Short-term borrowings
Debt Instrument [Line Items]
Interest rates	4.72%	4.72%	4.72%				6.54%	6.54%	6.54%
Short-term borrowings	$ 1,305						$ 348
Unamortized Carrying Value Adjustments	$ 0						$ 0