Ventures and Variable Interest Entities (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Millions		Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Variable Interest Entity [Line Items]
Cash and cash equivalents		$ 1,252	$ 967	$ 952	$ 780
Trade receivables - third party and affiliates		791	706
Property, plant and equipment (net of accumulated depreciation - 2016: $40; 2015: $10)		3,578	3,609
Accumulated depreciation		2,228	2,039
Intangible assets (net of accumulated amortization - 2016: $1; 2015: $0)		119	125
Accumulated amortization		542	528
Other assets		290	300
Total assets		8,757	8,586
Trade payables		591	587
Current liabilities		1,098	1,550
Deferred income taxes		139
Deferred income taxes			136
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash and cash equivalents		22	7
Trade receivables - third party and affiliates		5	6
Property, plant and equipment (net of accumulated depreciation - 2016: $40; 2015: $10)		744	772
Intangible assets (net of accumulated amortization - 2016: $1; 2015: $0)		26	27
Other assets		9	13
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Property, plant and equipment (net of accumulated depreciation - 2016: $40; 2015: $10)		65	73
Trade payables		51	47
Current installments of long-term debt		11	10
Long-term debt		97	109
Total liabilities		159	166
Maximum exposure to loss		250	268
Fairway Methanol LLC [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash and cash equivalents		22	7
Trade receivables - third party and affiliates		10	12
Property, plant and equipment (net of accumulated depreciation - 2016: $40; 2015: $10)		744	772
Accumulated depreciation		40	10
Intangible assets (net of accumulated amortization - 2016: $1; 2015: $0)		26	27
Accumulated amortization		1	0
Other assets		9	13
Total assets	[1]	811	831
Trade payables		15	9
Current liabilities	[2]	3	5
Long-term debt		5	5
Deferred income taxes		2
Deferred income taxes			2
Total liabilities		$ 25	$ 21

[1] Assets can only be used to settle the obligations of Fairway.

[2] Primarily represents amounts owed by Fairway to the Company for reimbursement of expenditures.