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v3.21.1

Debt and Financing Activities - Long-Term Debt (Details) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 03, 2020 USD ($) | Mar. 15, 2019 USD ($) | Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2020 EUR (€) | Mar. 31, 2019 USD ($) | Dec. 01, 2020 USD ($) | Nov. 30, 2020 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 7,148,000,000 | $ 7,387,000,000 |  |  |  |
Repayments of long-term debt |  |  | 1,040,000,000 | 298,000,000 |  | $ 1,112,000,000 |  |
Scheduled principal payments of long-term debt in 2022 |  |  | 742,000,000 |  |  |  |  |
Scheduled principal payments of long-term debt in 2023 |  |  | 838,000,000 |  |  |  |  |
Scheduled principal payments of long-term debt in 2024 |  |  | 1,100,000,000 |  |  |  |  |
Scheduled principal payments of long-term debt in 2025 |  |  | 34,000,000 |  |  |  |  |
Scheduled principal payments of long-term debt in 2026 |  |  | 1,200,000,000 |  |  |  |  |
Scheduled principal payments of long-term debt, thereafter |  |  | $ 3,200,000,000 |  |  |  |  |
Notes Payable |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Redemption price (percent) |  |  | 101.00% |  |  |  |  |
3.65% Notes due November 30, 2020 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 0 | 700,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 3.65% |  |  |  |  | 3.65%
Aggregate principal amount |  |  |  |  |  |  |  | $ 700,000,000
4.75% Notes due May 30, 2029 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 400,000,000 | 400,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 4.75% |  |  |  |  |
4.75% Notes due March 1, 2021 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 0 | 323,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 4.75% |  |  |  |  |
7.65% Debentures due March 1, 2027 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 167,000,000 | 167,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 7.65% |  |  |  |  |
6.00% Notes due March 1, 2041 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 282,000,000 | 282,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 6.00% |  |  |  |  |
4.88% Notes due March 15, 2044 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 411,000,000 | 411,000,000 |  |  |  |
Debt interest rate (percent) |  |  | 4.88% |  |  |  |  |
Floating Rate Euro Notes due February 12, 2020 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Repayments of long-term debt | € |  |  |  |  | € 250,000,000 |  |  |
2.28% Notes due March 15, 2019 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt interest rate (percent) |  | 2.28% |  |  |  |  |  |
Repayments of long-term debt |  | $ 1,100,000,000 |  |  |  |  |  |
0.90% Notes due December 3, 2025 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 500,000,000 | 0 |  |  |  |
Debt interest rate (percent) | 0.90% |  | 0.90% |  |  |  |  |
Aggregate principal amount | $ 500,000,000 |  |  |  |  |  |  |
Proceeds from issuance, net | $ 496,000,000 |  |  |  |  |  |  |
4.75% Notes Due March 1, 2021 | Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt interest rate (percent) |  |  |  |  |  |  | 4.75% |
Aggregate principal amount |  |  |  |  |  |  | $ 323,000,000 |
Long-term Debt, Current Maturities |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Total debt outstanding |  |  | $ 742,000,000 | $ 1,100,000,000 |  |  |  |

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