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Indebtedness - Summary of Indebtedness (Details) - USD ($) | Dec. 31, 2020 | Apr. 30, 2020 | Dec. 31, 2019 | Sep. 15, 2015
--- | --- | --- | --- | ---
Current portion: |  |  |  |
Current portion of notes payable | $ 0 |  | $ 1,495,800,000 |
Non-current portion: |  |  |  |
Non-current notes payable | 7,500,000,000.0 |  |  |
Non-current portion of notes payable | 7,426,200,000 |  | 4,459,000,000.0 |
Senior Notes |  |  |  |
Current portion: |  |  |  |
Current portion of notes payable | 0 |  | 1,495,800,000 |
Non-current portion: |  |  |  |
Non-current portion of notes payable | $ 7,426,200,000 |  | 4,459,000,000.0 |
Aggregate principal amount |  | $ 3,000,000,000.0 |  |
2.900% Senior Notes due September 15, 2020 |  |  |  |
Non-current portion: |  |  |  |
Interest rate on senior notes | 2.90% |  |  |
2.900% Senior Notes due September 15, 2020 | Senior Notes |  |  |  |
Current portion: |  |  |  |
2.900% Senior Notes due September 15, 2020 | $ 0 |  | 1,495,800,000 |
Non-current portion: |  |  |  |
Interest rate on senior notes | 2.90% |  |  |
Aggregate principal amount |  |  |  | $ 1,500,000,000
3.625% Senior Notes due September 15, 2022 |  |  |  |
Non-current portion: |  |  |  |
Interest rate on senior notes | 3.625% |  |  |
Aggregate principal amount | $ 1,000,000,000.0 |  |  |
3.625% Senior Notes due September 15, 2022 | Senior Notes |  |  |  |
Non-current portion: |  |  |  |
Non-current notes payable | $ 997,900,000 |  | 996,600,000 |
Interest rate on senior notes | 3.625% |  |  |
4.050% Senior Notes due September 15, 2025 |  |  |  |
Non-current portion: |  |  |  |
Interest rate on senior notes | 4.05% |  |  |
Aggregate principal amount | $ 1,750,000,000 |  |  |
4.050% Senior Notes due September 15, 2025 | Senior Notes |  |  |  |
Non-current portion: |  |  |  |
Non-current notes payable | $ 1,741,200,000 |  | 1,739,500,000 |
Interest rate on senior notes | 4.05% |  |  |
2.250% Senior Notes due May 1, 2030 | Senior Notes |  |  |  |
Non-current portion: |  |  |  |
Non-current notes payable | $ 1,491,100,000 |  | 0 |
Interest rate on senior notes | 2.25% | 2.25% |  |
Aggregate principal amount |  | $ 1,500,000,000 |  |
5.200% Senior Notes due September 15, 2045 |  |  |  |
Non-current portion: |  |  |  |
Interest rate on senior notes | 5.20% |  |  |
Aggregate principal amount | $ 1,750,000,000 |  |  |
5.200% Senior Notes due September 15, 2045 | Senior Notes |  |  |  |
Non-current portion: |  |  |  |
Non-current notes payable | $ 1,723,400,000 |  | 1,722,900,000 |
Interest rate on senior notes | 5.20% |  |  |
3.150% Senior Notes due May 1, 2050 | Senior Notes |  |  |  |
Non-current portion: |  |  |  |
Non-current notes payable | $ 1,472,600,000 |  | $ 0 |
Interest rate on senior notes | 3.15% | 3.15% |  |
Aggregate principal amount |  | $ 1,500,000,000 |  |

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