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Indebtedness - Narrative (Details) - USD ($) | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 31, 2020 | Dec. 31, 2020 | Apr. 30, 2020 | Sep. 15, 2015
Debt Instrument |  |  |  |
Redemptions percentage of 2015 notes |  | 100.00% |  |
Redemption percentage for change in control provision |  | 101.00% |  |
Debt instrument, term | 5 years |  |  |
Interest Expense | Interest rate swap |  |  |  |
Debt Instrument |  |  |  |
Gain (loss) on derivative instruments, net, pretax |  | $ 3,300,000 |  |
3.625% Senior Notes due September 15, 2022 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  | $ 1,000,000,000.0 |  |
Interest rate on senior notes |  | 3.625% |  |
Redemption percentage par value of senior notes |  | 99.92% |  |
4.050% Senior Notes due September 15, 2025 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  | $ 1,750,000,000 |  |
Interest rate on senior notes |  | 4.05% |  |
Redemption percentage par value of senior notes |  | 99.764% |  |
5.200% Senior Notes due September 15, 2045 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  | $ 1,750,000,000 |  |
Interest rate on senior notes |  | 5.20% |  |
Redemption percentage par value of senior notes |  | 99.294% |  |
2.900% Senior Notes due September 15, 2020 |  |  |  |
Debt Instrument |  |  |  |
Interest rate on senior notes |  | 2.90% |  |
Senior Notes |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  |  | $ 3,000,000,000.0 |
Redemptions percentage of 2015 notes |  | 100.00% |  |
Redemption percentage for change in control provision |  | 101.00% |  |
Senior Notes | 2020 Senior Notes |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  |  | 3,000,000,000.0 |
Costs associated with the senior Nnotes offerings |  | $ 24,400,000 |  |
Senior Notes | 2.250% Senior Notes due May 1, 2030 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  |  | $ 1,500,000,000 |
Interest rate on senior notes |  | 2.25% | 2.25% |
Redemption percentage par value of senior notes |  |  | 99.973% |
Senior Notes | 3.150% Senior Notes due May 1, 2050 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  |  | $ 1,500,000,000 |
Interest rate on senior notes |  | 3.15% | 3.15% |
Redemption percentage par value of senior notes |  |  | 99.174% |
Senior Notes | 2015 Senior Notes |  |  |  |
Debt Instrument |  |  |  |
Costs associated with the senior Nnotes offerings |  | $ 47,500,000 |  |
Senior Notes | 3.625% Senior Notes due September 15, 2022 |  |  |  |
Debt Instrument |  |  |  |
Interest rate on senior notes |  | 3.625% |  |
Senior Notes | 4.050% Senior Notes due September 15, 2025 |  |  |  |
Debt Instrument |  |  |  |
Interest rate on senior notes |  | 4.05% |  |
Senior Notes | 5.200% Senior Notes due September 15, 2045 |  |  |  |
Debt Instrument |  |  |  |
Interest rate on senior notes |  | 5.20% |  |
Senior Notes | 2.900% Senior Notes due September 15, 2020 |  |  |  |
Debt Instrument |  |  |  |
Senior notes aggregate principal amount |  |  |  | $ 1,500,000,000
Interest rate on senior notes |  | 2.90% |  |
Redemption percentage par value of senior notes |  |  |  | 99.792%
Pre-tax charge |  | $ 12,700,000 |  |
Senior Notes | 2.900% Senior Notes due September 15, 2020 | Interest Expense |  |  |  |
Debt Instrument |  |  |  |
Pre-tax charge |  | 9,400,000 |  |
Line of Credit | Revolving Credit Facility |  |  |  |
Debt Instrument |  |  |  |
Senior unsecured revolving credit facility maximum borrowing capacity | $ 1,000,000,000.0 |  |  |
Outstanding borrowings |  | $ 0 |  |

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