Financial Instruments (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Total Gross Assets & Liabilities [Domain]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	$ 4,736	$ 635
Advances to/receivables from equity companies	[2],[3]	7,790	8,670
Other long-term financial assets	[4]	2,116	2,119
Derivative liabilities	[5]	3,853	638
Long-term debt	[6]	33,256	25,789
Long-term obligations to equity companies	[2]	3,490	4,245
Other long-term financial liabilities	[7]	1,064	1,042
Net Carrying Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	171	102
Advances to/receivables from equity companies	[2],[3]	8,536	8,542
Other long-term financial assets	[4]	2,167	2,163
Derivative liabilities	[5]	216	70
Long-term debt	[6]	30,626	24,672
Long-term obligations to equity companies	[2]	4,024	3,988
Other long-term financial liabilities	[7]	1,104	1,058
Effect Of Counterparty Netting [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	(3,603)	(463)
Derivative liabilities	[5]	(3,603)	(463)
Effect Of Collateral Netting [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	(962)	(70)
Derivative liabilities	[5]	(34)	(105)
Difference In Carrying Value And Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Advances to/receivables from equity companies	[2],[3]	746	(128)
Other long-term financial assets	[4]	51	44
Long-term debt	[6]	(2,630)	(1,117)
Long-term obligations to equity companies	[2]	534	(257)
Other long-term financial liabilities	[7]	40	16
Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	4,565	533
Other long-term financial assets	[4]	1,141	1,145
Derivative liabilities	[5]	3,637	568
Long-term debt	[6]	33,128	25,652
Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative assets	[1]	171	102
Advances to/receivables from equity companies	[2],[3]	1,702	1,941
Derivative liabilities	[5]	216	70
Long-term debt	[6]	124	134
Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Advances to/receivables from equity companies	[2],[3]	6,088	6,729
Other long-term financial assets	[4]	975	974
Long-term debt	[6]	4	3
Long-term obligations to equity companies	[2]	3,490	4,245
Other long-term financial liabilities	[7]	$ 1,064	$ 1,042

[1] Included in the Balance Sheet lines: Notes and accounts receivable, less estimated doubtful amounts and Other assets, including intangibles, net

[2] Advances to/receivables from equity companies and long-term obligations to equity companies are mainly designated as hierarchy level 3 inputs. The fair value is calculated by discounting the remaining obligations by a rate consistent with the credit quality and industry of the company.

[3] Included in the Balance Sheet line: Investments, advances and long-term receivables

[4] Included in the Balance Sheet lines: Investments, advances and long-term receivables and Other assets, including intangibles, net

[5] Included in the Balance Sheet lines: Accounts payable and accrued liabilities and Other long-term obligations

[6] Excluding finance lease obligations

[7] Included in the Balance Sheet line: Other long-term obligations