Equity, Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax		$ (7)	$ (19)	$ 0
Losses on cash flow hedges:
Cost of sales		(65,962)	(73,861)	(118,141)
Total before tax		3,182	5,971	5,552
Tax benefit		(765)	(1,870)	(1,777)
Income from continuing operations		2,417	4,101	3,775
Accumulated Defined Benefit Plans Adjustment, Net Actuarial (Gain) Loss Component [Member]
Amortization of items related to defined benefit pension plans:
Reclassification from accumulated other comprehensive income (loss), current period, before tax	[1]	(48)	(62)	(34)
Tax (expense) benefit		18	22	12
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax		(30)	(40)	(22)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Cost (Credit) Component [Member]
Amortization of items related to defined benefit pension plans:
Reclassification from accumulated other comprehensive income (loss), current period, before tax	[1]	36	40	40
Tax (expense) benefit		(13)	(14)	(14)
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax		23	26	26
Accumulated Defined Benefit Plans Adjustment, Curtailment and Settlement Component [Member]
Amortization of items related to defined benefit pension plans:
Reclassification from accumulated other comprehensive income (loss), current period, before tax	[1]	0	(7)	(3)
Tax (expense) benefit			2	0
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax			(5)	(3)
Accumulated Defined Benefit Plans Adjustment [Member]
Amortization of items related to defined benefit pension plans:
Reclassification from accumulated other comprehensive income (loss), current period, before tax		(12)	(29)	3
Tax (expense) benefit		5	10	(2)
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax		(7)	(19)	1
Accumulated Net Gain (Loss) from Cash Flow Hedges [Member]
Amortization of items related to defined benefit pension plans:
Reclassification from accumulated other comprehensive income (loss), current period, before tax				(2)
Tax (expense) benefit				1
Gains (losses) reclassified out of accumulated other comprehensive income (loss)
Net of tax				(1)
Accumulated Net Gain (Loss) from Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Losses on cash flow hedges:
Total before tax		0	0	(2)
Tax benefit		0	0	1
Income from continuing operations		0	0	(1)
Accumulated Net Gain (Loss) from Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member] | Commodity Contracts [Member]
Losses on cash flow hedges:
Cost of sales		$ 0	$ 0	$ (2)

[1] These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost, as further discussed in Note 12. Net periodic benefit cost is reflected in operating expenses and general and administrative expenses.