Fair Value Measurements - Fair Value of Short-term Investments and Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Vendor Financing Arrangement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Term loans	$ 353	$ 25
Level 3 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred purchase price assets	841	781
Level 3 \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred purchase price assets	841	781
Level 1 \| Carrying Amount \| Secured Term Loan Facility \| Third Party
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Term loans	3,896	0
Level 1 \| Carrying Amount \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	34,354	10,958
Level 1 \| Carrying Amount \| Senior Notes \| Third Party
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	27,998	0
Level 1 \| Fair Value \| Secured Term Loan Facility \| Third Party
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Term loans	4,000	0
Level 1 \| Fair Value \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	35,751	11,479
Level 1 \| Fair Value \| Senior Notes \| Third Party
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	30,909	0
Level 2 \| Carrying Amount \| Secured Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Term loans	0	4,000
Level 2 \| Carrying Amount \| Senior Notes \| Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	5,941	9,986
Level 2 \| Fair Value \| Secured Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Term loans	0	4,000
Level 2 \| Fair Value \| Senior Notes \| Affiliates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 6,231	$ 10,366

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- Definition

Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

+ References

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Fair value portion of notes payable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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