Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2022	Oct. 01, 2021	Sep. 30, 2021
Debt Instrument [Line Items]
Finance lease obligation	$ 12		$ 10
Borrowings and securitization	95		0
Subtotal	1,139		1,027
Less: short-term debt	(114)		(19)
Long-term debt	1,025		1,008
Convertible Notes
Debt Instrument [Line Items]
Unamortized discount on convertible notes	$ 0		(23)
3.25 percent convertible notes due 2037 \| Convertible Notes
Debt Instrument [Line Items]
Interest rate	3.25%	3.25%
Debt	$ 321		321
4.50 percent notes due 2028 \| Senior Notes
Debt Instrument [Line Items]
Interest rate	4.50%
Long-term debt outstanding	$ 271		270
6.25 percent notes due 2025 \| Senior Notes
Debt Instrument [Line Items]
Interest rate	6.25%
Long-term debt outstanding	$ 296		296
Term loan due 2024 \| Term Loan
Debt Instrument [Line Items]
Long-term debt outstanding	$ 144		$ 153

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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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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Amount, after accumulated amortization, of debt discount.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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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 of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, including portion classified as current.

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This is the principal amount outstanding for securitized loans only (across all types of loans).

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