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v3.20.2

Debt (Narrative) (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Jan. 31, 2020 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Apr. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) | Jun. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | May 31, 2020 USD ($) | Apr. 01, 2019 USD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2019 EUR (€) | Jan. 31, 2019 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commercial paper outstanding |  |  |  |  |  |  | $ 0 |  | $ 0 |  |  |  |  |  |
Payments for early extinguishment of debt |  |  |  |  |  |  |  |  | 0 | $ 585,000,000 |  |  |  |  |
April 2020 New Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt facilities, maximum borrowing capacity | $ 1,000,000,000 |  |  |  |  |  | $ 0 |  | $ 0 |  |  |  |  |  |
Term of debt | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |  |
2.250% Senior Debt Obligations Due 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  | 2.25% |  | 2.25% |  |  |  |  |  |
1.349% Senior Debt Obligations Due 2026 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  | 1.349% |  | 1.349% |  |  |  |  |  |
1.979% Senior Debt Obligations Due 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  | 1.979% |  | 1.979% |  |  |  |  |  |
Commercial Paper |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term debt |  |  |  |  |  |  | $ 1,500,000,000 |  | $ 1,500,000,000 |  |  |  |  |  |
Jardine Lloyd Thompson Group plc |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  | $ 553,000,000 | $ 450,000,000 |  |  |  |  |  |  |  |  |
Debt assumed in acquisition |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000,000 |  |  |
Payments for early extinguishment of debt |  |  |  |  |  |  |  | $ 32,000,000 |  |  |  |  |  |  |
Revolving Credit Facility | Amended Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt facilities, maximum borrowing capacity |  |  |  |  |  |  | 1,800,000,000 |  | $ 1,800,000,000 |  |  |  |  |  |
Term of debt |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |
Long-term line of credit |  | $ 1,000,000,000 |  |  |  |  | 0 |  | $ 0 |  |  |  |  |  |
Term Loan Facility | $500 Million One-Year Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt facilities, maximum borrowing capacity |  |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  |  |  | 0 |  | 0 |  |  |  |  |  |
Repayments of debt |  |  |  |  |  |  | 500,000,000 |  |  |  |  |  |  |  |
Term Loan Facility | $500 Million Two-Year Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt facilities, maximum borrowing capacity |  |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |
Long-term line of credit |  |  |  |  |  |  | 500,000,000 |  | 500,000,000 |  |  |  |  |  |
Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt |  | $ 500,000,000 |  | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000,000
Senior Notes | 2.250% Senior Debt Obligations Due 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  | $ 750,000,000 |  |  |  |
Interest rate |  |  |  |  |  |  |  |  |  |  | 2.25% |  |  |  |
Senior Notes | 1.349% Senior Debt Obligations Due 2026 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount | € |  |  |  |  |  |  |  |  |  |  |  |  |  | € 550,000,000 |
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  | 1.349% | 1.349% |
Senior Notes | 1.979% Senior Debt Obligations Due 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount | € |  |  |  |  |  |  |  |  |  |  |  |  |  | € 550,000,000 |
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  | 1.979% | 1.979% |
Senior Notes | Senior Debt Obligations 4.375% Due 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  | $ 1,500,000,000 |  | $ 1,500,000,000 |  |  |  | $ 250,000,000 |  | 1,250,000,000
Interest rate |  |  |  |  |  |  | 4.375% |  | 4.375% |  |  |  |  |  |
Senior Notes | Senior Debt Obligations 3.50% Due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 700,000,000
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.50%
Senior Notes | Senior Debt Obligations 3.875% Due 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000,000
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.875%
Senior Notes | Senior Debt Obligations 4.75% Due 2039 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.75%
Senior Notes | Senior Debt Obligations 4.90% Due 2049 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,250,000,000
Interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.90%
Senior Notes | Floating Rate Senior Notes Due 2021 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 300,000,000
Senior Notes | Jardine Lloyd Thompson Group plc |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument face amount | € |  |  |  |  |  |  |  |  |  |  |  |  |  | € 1,100,000,000 |

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