Long-term Debt, Short-term Borrowings and Finance Lease Obligations - Maturities Of Our Debt and Finance Leases (Details) $ in Millions	Sep. 30, 2021 USD ($)
Debt Disclosure [Abstract]
Remainder of 2021	$ 130
2022	355
2023	564
2024	332
2025	192
Thereafter	$ 2,600

Scheduled maturities, Remainder of Fiscal Year, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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Scheduled maturities, Year 2, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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Scheduled maturities, Year 3, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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Scheduled maturities, Year 4, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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Scheduled maturities, Year 5, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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Scheduled maturities, after Year 5, short-term borrowings, long-term debt, and finance lease obligations

No definition available.

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No definition available.

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