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Debt - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Aug. 31, 2020 | May 31, 2020
Senior Unsecured Notes |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Interest expense | $ 11,100,000 | $ 33,300,000 |  |
Bridge Facility | Bridge Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt, principal amount |  |  |  | $ 1,500,000,000
1.750% Senior Notes due September 2030 | Senior Unsecured Notes |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt, principal amount |  |  | $ 1,250,000,000 |
2.800% Senior Notes due September 2050 | Senior Unsecured Notes |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt, principal amount |  |  | $ 750,000,000 |

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