Long-Term Debt (Details) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2022 USD ($)	Mar. 31, 2022 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	101.00%
Change in Commercial Paper	$ 2,200	$ 2,200
2.625 Percent Notes Due December 2021
Debt Instrument [Line Items]
Notes interest rate, percentage	2.625%	2.625%
Repayments of Debt		$ 500
2.0 Percent Notes due December 2028
Debt Instrument [Line Items]
Notes interest rate, percentage	2.00%	2.00%
Proceeds from Issuance of Debt	$ 1,000
2.2 Percent Notes due December 2031
Debt Instrument [Line Items]
Notes interest rate, percentage	2.20%	2.20%
Proceeds from Issuance of Debt	$ 1,000
2.8 Percent Notes due December 2051
Debt Instrument [Line Items]
Notes interest rate, percentage	2.80%	2.80%
Proceeds from Issuance of Debt	$ 1,000

Increase (Decrease) in Commercial Paper

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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