Ventures and Variable Interest Entities (Schedule of Variable Interest Entities) (Details) - USD ($) $ in Millions		Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Cash and cash equivalents		$ 708	$ 576	$ 511	$ 638
Trade receivables - third party and affiliates		1,156	986
Nontrade Receivables, Current		289	244
Property, plant and equipment (net of accumulated depreciation - 2018: $110; 2017: $90)		3,724	3,762
Accumulated depreciation		2,696	2,584
Intangible assets (net of accumulated amortization - 2018: $3; 2017: $2)		325	301
Accumulated amortization		592	591
Other assets		392	338
Total assets		9,789	9,538
Trade payables		819	807
Other liabilities		1,610	1,559
Restructuring reserves (Note 14)		7
Deferred income taxes		248	211
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash and cash equivalents		18	19
Trade receivables - third party and affiliates		8	5
Nontrade Receivables, Current		0	0
Property, plant and equipment (net of accumulated depreciation - 2018: $110; 2017: $90)		676	697
Intangible assets (net of accumulated amortization - 2018: $3; 2017: $2)		24	25
Other assets		6	6
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Property, plant and equipment (net of accumulated depreciation - 2018: $110; 2017: $90)		48	53
Trade payables		36	25
Current installments of long-term debt		14	18
Long-term debt		68	76
Total liabilities		118	119
Maximum exposure to loss		160	164
Fairway Methanol LLC [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash and cash equivalents		18	19
Trade receivables - third party and affiliates		15	9
Property, plant and equipment (net of accumulated depreciation - 2018: $110; 2017: $90)		676	697
Accumulated depreciation		110	90
Intangible assets (net of accumulated amortization - 2018: $3; 2017: $2)		24	25
Accumulated amortization		3	2
Other assets		6	6
Total assets	[1]	739	756
Trade payables		9	16
Other liabilities	[2]	5	4
Long-term debt		5	5
Deferred income taxes		3	3
Total liabilities		22	28
Acetyl Intermediates [Member]
Variable Interest Entity [Line Items]
Restructuring reserves (Note 14)		3
Plant/Office Closures [Member]
Variable Interest Entity [Line Items]
Restructuring reserves (Note 14)		2	2
Plant/Office Closures [Member] | Acetyl Intermediates [Member]
Variable Interest Entity [Line Items]
Restructuring reserves (Note 14)		$ 2	$ 2

[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.