v3.20.1
Derivative and Financial Instruments - Financial Instruments at cost (Details) - USD ($)
$ in Millions
Mar. 31, 2020
Dec. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest $ 3,889 $ 5,079
Short-term investments carried at cost plust accrued interest 3,630 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 550 759
Demand Deposits [Member]    
Schedule of Held-to-maturity Securities [Line Items]    
Cash and Cash Equivalents, carried at cost plus accrued interest 1,387 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 1,935 2,030
Short-term investments carried at cost plust accrued interest 3,345 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 274 465
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 11 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
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 17 394
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