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v3.20.4

Debt (Narrative) (Details) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) | Apr. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Jan. 31, 2020 USD ($) | Sep. 30, 2019 USD ($) | Oct. 31, 2018 | Sep. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | May 31, 2020 USD ($) | Apr. 01, 2019 USD ($) | Mar. 31, 2019 EUR (€) | Jan. 31, 2019 USD ($) | Oct. 01, 2018 USD ($) | Sep. 30, 2018 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term debt | $ 517,000,000 |  |  |  |  |  |  |  | $ 517,000,000 | $ 1,215,000,000 |  |  |  |  |  |  |
Commercial paper outstanding | 0 |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |
Payments for early extinguishment of debt |  |  |  |  |  |  |  |  | 0 | 585,000,000 | $ 0 |  |  |  |  |  |
Repayments of principal in 2021 | 517,000,000 |  |  |  |  |  |  |  | 517,000,000 |  |  |  |  |  |  |  |
Repayments of principal in 2022 | 516,000,000 |  |  |  |  |  |  |  | 516,000,000 |  |  |  |  |  |  |  |
Repayments of principal in 2023 | 619,000,000 |  |  |  |  |  |  |  | 619,000,000 |  |  |  |  |  |  |  |
Repayments of principal in 2024 | 1,600,000,000 |  |  |  |  |  |  |  | 1,600,000,000 |  |  |  |  |  |  |  |
Repayments of principal in 2025 | 518,000,000 |  |  |  |  |  |  |  | 518,000,000 |  |  |  |  |  |  |  |
April 2020 New Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, borrowing capacity |  | $ 1,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Debt Facilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, amount outstanding | 0 |  |  |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  |
Debt instrument, unused borrowing capacity | 573,000,000 |  |  |  |  |  |  |  | 573,000,000 | 598,000,000 |  |  |  |  |  |  |
Commercial Paper |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term debt | 1,500,000,000 |  |  |  |  |  |  |  | 1,500,000,000 |  |  |  |  |  |  |  |
Term loan facility | $500 Million One-Year Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt | 500,000,000 |  |  |  |  |  | $ 500,000,000 | $ 1,000,000,000 |  |  |  |  |  |  |  |  |
Revolving credit facility, borrowing capacity |  |  |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term |  |  |  | 1 year |  |  | 1 year |  |  |  |  |  |  |  |  |  |
Revolving credit facility, amount outstanding | $ 0 |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |
Term loan facility | $500 Million Two-Year Term Loan Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, borrowing capacity |  |  |  | $ 500,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term | 2 years |  |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility | Amended Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,800,000,000 | $ 1,500,000,000
Debt instrument, term |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, amount outstanding | $ 0 |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |  |  |
JLT Transaction |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness assumed |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000,000 |  |  |  |
Payments for early extinguishment of debt |  |  |  |  |  |  |  |  |  | 32,000,000 |  |  |  |  |  |  |
Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt | 700,000,000 |  | $ 500,000,000 |  | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000,000 |  |
Senior Notes | 2.250% Senior Debt Obligations Due 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, amount |  |  |  |  |  |  |  |  |  |  |  | $ 750,000,000 |  |  |  |  |
Interest rate |  |  |  |  |  |  |  |  |  |  |  | 2.25% |  |  |  |  |
Senior Notes | JLT Transaction |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, amount |  |  |  |  |  |  |  |  |  | $ 6,500,000,000 |  |  |  | € 1,100,000,000 |  |  |
Floating Rate Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of debt | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: 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)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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