v3.20.2
Derivative and Financial Instruments - Financial Instruments at cost (Details) - USD ($)
$ in Millions
Jun. 30, 2020
Dec. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest $ 2,903 $ 5,079
Short-term investments, carried at cost plust accrued interest 3,705 2,929
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 3 0
Cash [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 575 759
Demand Deposits [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 917 1,483
Short-term investments, carried at cost plust accrued interest 0 0
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Time Deposits [Member] | Remaining maturities from 1 to 90 days [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 1,396 2,030
Short-term investments, carried at cost plust accrued interest 2,339 1,395
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Time Deposits [Member] | Remaining maturities from 91 to 180 days [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 0 0
Short-term investments, carried at cost plust accrued interest 1,302 465
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Time Deposits [Member] | Remaining maturities within one year [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 0 0
Short-term investments, carried at cost plust accrued interest 14 0
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Time Deposits [Member] | Remaining Maturities Greater Than One Year Through Five Years [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 0 0
Short-term investments, carried at cost plust accrued interest 0 0
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 3 0
Commercial Paper [Member] | Remaining maturities from 1 to 90 days [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 0 413
Short-term investments, carried at cost plust accrued interest 0 1,069
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Commercial Paper [Member] | Remaining maturities from 91 to 180 days [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 0 0
Short-term investments, carried at cost plust accrued interest 50 0
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest 0 0
Government obligations [Member] | Remaining maturities from 1 to 90 days [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 15 394
Short-term investments, carried at cost plust accrued interest 0 0
Accounts and Financing Receivable, after Allowance for Credit Loss, Noncurrent at cost plus accrued interest $ 0 $ 0