Fair Value Measurements (Fair Value of Assets and Liabilities Measured on a Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023
Transaction Data System Investment
Assets:
Equity Method Investment, Ownership Percentage	16.00%
Recurring
Assets:
Cash equivalents	$ 1,708		$ 1,253
Other investments	102		101
Forward Contract	(73)		(73)
Liabilities:
Forward Contract	(73)		(73)
Level 1 \| Recurring
Assets:
Cash equivalents	1,708		1,253
Other investments	102		101
Forward Contract	0		0
Liabilities:
Forward Contract	0		0
Level 2 \| Recurring
Assets:
Cash equivalents	0		0
Other investments	0		0
Forward Contract	(73)		(73)
Liabilities:
Forward Contract	(73)		(73)
Level 3 \| Recurring
Assets:
Cash equivalents	0		0
Other investments	0		0
Forward Contract	0		0
Liabilities:
Forward Contract	$ 0		$ 0
Level 3 \| Fair Value, Nonrecurring \| Transaction Data System Investment
Assets:
Equity Method Investments, Fair Value Disclosure		$ 147

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480463/815-10-45-5

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

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Fair value portion of investments accounted under the equity method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2E

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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