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

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Publisher FASB
-Name Accounting Standards Codification
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Debt and Financing Activities - Schedule Of Long-Term Debt (Details) - USD ($)	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Feb. 16, 2018	Feb. 12, 2018	Feb. 07, 2018
Debt Instrument [Line Items]
Total debt	$ 7,595,000,000	$ 7,880,000,000
Less: Current portion	(330,000,000)	(1,129,000,000)
Total long-term debt	7,265,000,000	6,751,000,000
Notes \| 2.28% Notes due March 15, 2019
Debt Instrument [Line Items]
Total debt	$ 0	1,100,000,000
Debt interest rate (percent)	2.28%
Debt maturity date	Mar. 15, 2019
Notes \| 3.65% Notes due November 30, 2020
Debt Instrument [Line Items]
Total debt	$ 700,000,000	0
Debt interest rate (percent)	3.65%
Debt maturity date	Nov. 30, 2020
Notes \| 4.75% Notes due March 1, 2021
Debt Instrument [Line Items]
Total debt	$ 323,000,000	323,000,000
Debt interest rate (percent)	4.75%				4.75%
Debt maturity date	Mar. 01, 2021
Notes \| 2.70% Notes due December 15, 2022
Debt Instrument [Line Items]
Total debt	$ 400,000,000	400,000,000
Debt interest rate (percent)	2.70%
Debt maturity date	Dec. 15, 2022
Notes \| 2.85% Notes due March 15, 2023
Debt Instrument [Line Items]
Total debt	$ 400,000,000	400,000,000
Debt interest rate (percent)	2.85%
Debt maturity date	Mar. 15, 2023
Notes \| 3.80% Notes due March 15, 2024
Debt Instrument [Line Items]
Total debt	$ 1,100,000,000	1,100,000,000
Debt interest rate (percent)	3.80%
Debt maturity date	Mar. 15, 2024
Notes \| 7.65% Debentures due March 1, 2027
Debt Instrument [Line Items]
Total debt	$ 167,000,000	167,000,000
Debt interest rate (percent)	7.65%				7.65%
Debt maturity date	Mar. 01, 2027
Notes \| 3.95% Notes due February 16, 2028
Debt Instrument [Line Items]
Total debt	$ 600,000,000	600,000,000
Debt interest rate (percent)	3.95%		3.95%
Debt maturity date	Feb. 16, 2028
Notes \| 4.75% Notes due May 30, 2029
Debt Instrument [Line Items]
Total debt	$ 400,000,000	0
Debt interest rate (percent)	4.75%
Debt maturity date	May 30, 2029
Notes \| 6.00% Notes due March 1, 2041
Debt Instrument [Line Items]
Total debt	$ 282,000,000	282,000,000
Debt interest rate (percent)	6.00%				6.00%
Debt maturity date	Mar. 01, 2041
Notes \| 4.88% Notes due March 15, 2044
Debt Instrument [Line Items]
Total debt	$ 411,000,000	411,000,000
Debt interest rate (percent)	4.88%				4.88%
Debt maturity date	Mar. 15, 2044
Notes \| Floating Rate Euro Notes due February 12, 2020
Debt Instrument [Line Items]
Total debt	$ 280,000,000	337,000,000
Notes \| 0.63% Euro Notes due August 17, 2021
Debt Instrument [Line Items]
Total debt	$ 673,000,000	695,000,000
Debt interest rate (percent)	0.63%
Debt maturity date	Aug. 17, 2021
Notes \| 1.50% Euro Notes due November 17, 2025
Debt Instrument [Line Items]
Total debt	$ 670,000,000	691,000,000
Debt interest rate (percent)	1.50%
Debt maturity date	Nov. 17, 2025
Notes \| 1.63% Euro Notes due October 30, 2026
Debt Instrument [Line Items]
Total debt	$ 560,000,000	669,000,000
Debt interest rate (percent)	1.63%			1.63%
Debt maturity date	Oct. 30, 2026
Notes \| 3.13% Sterling Notes due February 17, 2029
Debt Instrument [Line Items]
Total debt	$ 586,000,000	630,000,000
Debt interest rate (percent)	3.13%
Debt maturity date	Feb. 17, 2029
Lease and other obligations
Debt Instrument [Line Items]
Total debt	$ 43,000,000	75,000,000
Commercial Paper
Debt Instrument [Line Items]
Total debt	$ 0	$ 0