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Debt and Other Commitments - Narrative (Details) |  |  |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Mar. 23, 2021 USD ($) | Mar. 08, 2021 USD ($) | Sep. 20, 2020 USD ($) | Aug. 31, 2018 USD ($) day $ / shares | Jan. 02, 2022 USD ($) renewal | Jan. 03, 2021 USD ($) | Dec. 29, 2019 USD ($) | Aug. 21, 2018 | Jun. 30, 2014 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Additional paid in capital, net of tax |  |  |  |  | $ 8,938,000,000 | $ 3,815,000,000 |  |  |
Bridge facility |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument term |  |  | 364 days |  |  |  |  |  |
Term Notes |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Net proceeds from issuance, after deducting offering expenses payable | $ 992,000,000 |  |  |  |  |  |  |  |
Redemption price, percentage |  |  |  |  | 100.00% |  |  |  |
Interest expense recognized |  |  |  |  | $ 14,000,000 |  |  |  |
Term Notes | Term Notes Due 2023 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal amount | $ 500,000,000 |  |  |  | 500,000,000 |  |  |  |
Interest rate on convertible senior notes | 0.55% |  |  |  |  |  |  |  |
Term Notes | Term Notes Due 2031 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal amount | $ 500,000,000 |  |  |  | $ 500,000,000 |  |  |  |
Interest rate on convertible senior notes | 2.55% |  |  |  |  |  |  |  |
Line of Credit | The Credit Agreement |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument term, number of renewal | renewal |  |  |  |  | 2 |  |  |  |
Debt instrument, renewal term |  |  |  |  | 1 year |  |  |  |
Borrowings outstanding |  |  |  |  | $ 0 |  |  |  |
Line of Credit | Revolving Credit Facility | The Credit Agreement |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument term |  | 5 years |  |  |  |  |  |  |
Maximum borrowing capacity |  | $ 750,000,000 |  |  |  |  |  |  |
Line of Credit | Swingline Borrowings | The Credit Agreement |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  | 40,000,000 |  |  |  |  |  |  |
Line of Credit | Letter of Credit | The Credit Agreement |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  | 50,000,000 |  |  |  |  |  |  |
Unsecured Debt | The Credit Agreement |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, face amount, optional increase in additional borrowings |  | $ 250,000,000 |  |  |  |  |  |  |
Debt instrument, covenant, minimum debt to EBITDA ratio |  |  |  |  | 3.50 |  |  |  |
Debt instrument, covenant, minimum debt to EBITDA ratio upon consummation of acquisition |  |  |  |  | 4.00 |  |  |  |
Unsecured Debt | Bridge facility |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal amount |  |  | $ 1,000,000,000 |  |  |  |  |  |
Convertible Senior Notes |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Interest expense recognized |  |  |  |  | $ 36,000,000 | 46,000,000 | $ 51,000,000 |  |
Carrying value of equity component of convertible senior notes, net of debt issuance costs |  |  |  |  | 126,000,000 | 213,000,000 |  |  |
Convertible Senior Notes | 2023 Notes |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal amount |  |  |  | $ 750,000,000 | 750,000,000 | 750,000,000 |  |  |
Interest rate on convertible senior notes |  |  |  |  |  |  |  | 0.00% |
Net proceeds from issuance, after deducting offering expenses payable |  |  |  | $ 735,000,000 |  |  |  |  |
Redemption price, percentage |  |  |  | 100.00% |  |  |  |  |
Conversion price (in dollars per share) | $ / shares |  |  |  | $ 457.77 |  |  |  |  |
Threshold common stock trading days | day |  |  |  | 20 |  |  |  |  |
Threshold consecutive common stock trading days | day |  |  |  | 30 |  |  |  |  |
Threshold percentage of common stock price trigger |  |  |  | 130.00% |  |  |  |  |
Threshold note trading days | day |  |  |  | 5 |  |  |  |  |
Threshold consecutive note trading days | day |  |  |  | 10 |  |  |  |  |
Threshold percentage of note price trigger |  |  |  | 98.00% |  |  |  |  |
Observation period |  |  |  | 20 days |  |  |  |  |
Effective conversion rate divided period |  |  |  | 20 days |  |  |  |  |
Convertible stock price trigger (in dollars per share) | $ / shares |  |  |  | $ 595.10 |  |  |  |  |
Effective interest rate used to measure fair value of convertible senior note |  |  |  | 3.70% |  |  |  |  |
Debt, fair value |  |  |  | $ 624,000,000 |  |  |  |  |
Additional paid in capital, before tax |  |  |  | 126,000,000 |  |  |  |  |
Additional paid in capital, net of tax |  |  |  | $ 93,000,000 |  |  |  |  |
Convertible Senior Notes | 2021 Notes |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal amount |  |  |  |  | $ 0 | $ 517,000,000 |  |  | $ 517,000,000
Interest rate on convertible senior notes |  |  |  |  |  |  |  |  | 0.50%
Effective interest rate used to measure fair value of convertible senior note |  |  |  |  |  |  |  |  | 3.50%

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