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Indebtedness (Details) - USD ($) | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Apr. 30, 2020 | Sep. 15, 2015
Debt Instrument [Line Items] |  |  |  |
Payments of financing costs | $ 24,400,000 |  |  |
Derivative, gain on derivative | $ 3,300,000 | $ 0 |  |
2.250% Senior Notes due May 1, 2030 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior notes interest rate | 2.25% |  |  |
3.150% Senior Notes due May 1, 2050 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior notes interest rate | 3.15% |  |  |
Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  | $ 3,000,000,000.0 |
Debt instrument, redemption price, percentage | 100.00% |  |  |
Debt instrument, make whole provision redemption price, percentage | 101.00% |  |  |
Senior Notes | 2.250% Senior Notes due May 1, 2030 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  | $ 1,500,000,000 |
Senior notes interest rate |  |  | 2.25% |
Percentage par value of senior notes |  |  | 99.973% |
Senior Notes | 3.150% Senior Notes due May 1, 2050 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  | $ 1,500,000,000 |
Senior notes interest rate |  |  | 3.15% |
Percentage par value of senior notes |  |  | 99.174% |
Senior Notes | 2.90% Senior Notes Due Sept 15, 2020 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  |  | $ 1,500,000,000
Senior notes interest rate |  |  |  | 2.90%
Percentage par value of senior notes |  |  |  | 99.792%
Payment of early call premium and write off of remaining unamortized debt issuance costs | $ 12,700,000 |  |  |
Interest Expense | Senior Notes | 2.90% Senior Notes Due Sept 15, 2020 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Pre-tax charge, payment of early call premium and write off of remaining unamortized debt issuance costs, net of derivative gain | 9,400,000 |  |  |
Interest Expense | Interest rate swap |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, gain on derivative | $ 3,300,000 |  |  |

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