Derivative and Financial Instruments (Financial Instruments - Net Carrying Amount of Held to Maturity Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Cash and Cash Equivalents, carried at cost plus accrued interest	$ 5,018	$ 2,978
Short-term investments, carried at cost plus accrued interest	225	3,320
Investments and long-term receivables carried at cost plus accrued interest	0	1
Cash [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cash and Cash Equivalents, carried at cost plus accrued interest	670	597
Demand Deposits [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cash and Cash Equivalents, carried at cost plus accrued interest	1,554	1,133
Time Deposits [Member] \| 1 to 90 days [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cash and Cash Equivalents, carried at cost plus accrued interest	2,363	1,225
Short-term investments, carried at cost plus accrued interest	217	2,859
Time Deposits [Member] \| 91 to 180 days [Member]
Schedule of Held-to-maturity Securities [Line Items]
Short-term investments, carried at cost plus accrued interest	4	448
Time Deposits [Member] \| Within one year [Member]
Schedule of Held-to-maturity Securities [Line Items]
Short-term investments, carried at cost plus accrued interest	4	13
Time Deposits [Member] \| One year through five years [Member]
Schedule of Held-to-maturity Securities [Line Items]
Investments and long-term receivables carried at cost plus accrued interest	0	1
U.S. Government Obligations [Member] \| 1 to 90 days [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cash and Cash Equivalents, carried at cost plus accrued interest	431	23
Short-term investments, carried at cost plus accrued interest	$ 0	$ 0