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Debt - Narrative (Details) |  | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
May 29, 2020 USD ($) | Sep. 30, 2020 USD ($) credit_facility | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) credit_facility | Sep. 30, 2019 USD ($) | Sep. 30, 2020 EUR (€) credit_facility | Aug. 05, 2020 EUR (€) | Jun. 30, 2020 | May 12, 2020 USD ($) | Mar. 31, 2020 USD ($) | Feb. 27, 2020 USD ($) | Feb. 26, 2020 USD ($) | Nov. 15, 2019 USD ($) | May 02, 2019 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on extinguishment of debt |  | $ 0 | $ 0 | $ 7,000,000 | $ 0 |  |  |  |  |  |  |  |  |
Number of credit facilities | credit_facility |  | 2 |  | 2 |  | 2 |  |  |  |  |  |  |  |
Borrowings under credit facilities |  | $ 0 |  | $ 0 |  |  |  |  |  |  |  |  |  |
Commercial paper |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | 1,650,000,000 |  | 1,650,000,000 |  |  |  |  |  |  |  |  |  |
Line of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, available credit |  | 1,650,000,000 |  | 1,650,000,000 |  |  |  |  |  |  |  |  |  |
Line of Credit | Credit Facility Expiring February 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | 900,000,000 |  | 900,000,000 |  |  |  |  |  |  |  |  |  |
Line of Credit | Credit Facility Expiring October 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | 750,000,000 |  | 750,000,000 |  |  |  |  |  |  | $ 750,000,000 | $ 400,000,000 |  |
Line of credit facility, increase in maximum borrowing capacity |  |  |  |  |  |  |  |  |  |  | $ 350,000,000 |  |  |
5.00% Senior Notes Due September 2020 | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate percentage (as a percent) | 5.00% |  |  |  |  |  |  | 5.00% |  |  |  |  |  |
Debt face value | $ 600,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on extinguishment of debt | $ 7,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2.80% Senior Notes Due May 2030 | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate percentage (as a percent) |  |  |  |  |  |  |  |  | 2.80% |  |  |  |  |
Debt face value |  |  |  |  |  |  |  |  | $ 1,000,000,000 |  |  |  |  |
2.80% Senior Notes Due March 2021 | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate percentage (as a percent) |  |  |  |  |  |  |  |  |  | 2.80% |  |  |  |
Debt face value |  |  |  |  |  |  |  |  |  | $ 400,000,000 |  |  |  |
2.20% Senior Notes Due November 2022 | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate percentage (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  | 2.20% |
Debt face value |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000 |
3.75% Senior Notes Due May 2029 | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate percentage (as a percent) |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.75%
Debt face value |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 750,000,000
U.S. Program | Commercial paper |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | $ 900,000,000 |  | $ 900,000,000 |  |  |  |  |  |  |  |  |  |
European Program | Commercial paper |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | € |  |  |  |  |  | € 625,000,000 | € 625,000,000 |  |  |  |  |  |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12355-112629 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12317-112629 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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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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