Debt - Summary of Term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 26, 2020	Sep. 26, 2020
Debt Instrument [Line Items]
Total term debt	$ 105,863	$ 106,078
Unamortized premium/(discount) and issuance costs, net	(305)	(314)
Hedge accounting fair value adjustments	1,485	1,676
Less: Current portion of term debt	(7,762)	(8,773)
Total non-current portion of term debt	99,281	98,667
2013 – 2020 debt issuances \| Floating-rate notes
Debt Instrument [Line Items]
Total term debt	$ 2,250	$ 2,250
Debt instrument, maturity year (calendar), start	2021
Debt instrument, maturity year (calendar), end	2022
2013 – 2020 debt issuances \| Floating-rate notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, effective interest rate	0.56%	0.60%
2013 – 2020 debt issuances \| Floating-rate notes \| Maximum
Debt Instrument [Line Items]
Debt instrument, effective interest rate	1.34%	1.39%
2013 – 2020 debt issuances \| Fixed-rate notes
Debt Instrument [Line Items]
Total term debt	$ 103,613	$ 103,828
Debt instrument, maturity year (calendar), start	2021
Debt instrument, maturity year (calendar), end	2060
2013 – 2020 debt issuances \| Fixed-rate notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, stated interest rate	0.00%
Debt instrument, effective interest rate	0.03%	0.03%
2013 – 2020 debt issuances \| Fixed-rate notes \| Maximum
Debt Instrument [Line Items]
Debt instrument, stated interest rate	4.65%
Debt instrument, effective interest rate	4.78%	4.78%

Latest year the outstanding debt instruments are required to be repaid.

No definition available.

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- Definition

Earliest year the outstanding debt instruments are required to be repaid.

+ References

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- Definition

Amount as of the balance sheet date of the adjustment to the carrying value of an interest bearing hedged item made under an interest rate fair value hedge.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

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- Definition

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

+ References

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-Publisher FASB
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-Topic 210
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- Definition

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.

+ References

No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

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.

+ References

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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