Consolidating Guarantor Financial Information (Schedule of Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 940	$ 726
Investing Activities
Capital expenditures on property, plant and equipment	(186)	(168)
Acquisitions, net of cash acquired	0	(3)
Proceeds from sale of businesses and assets, net	8	0
Capital expenditures related to Fairway Methanol LLC	0	(263)
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	0	0
Other, net	(14)	(27)
Net cash provided by (used in) investing activities	(192)	(461)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(347)	346
Proceeds from short-term borrowings	39	40
Repayments of short-term borrowings	(76)	(60)
Proceeds from long-term debt	1,509	0
Repayments of long-term debt	(1,095)	(18)
Purchases of treasury stock, including related fees	(300)	(420)
Dividends to parent	0	0
Contributions from parent	0	0
Stock option exercises	3	2
Series A common stock dividends	(150)	(131)
Return of capital to parent	0	0
(Distributions to) contributions from noncontrolling interests	(15)	187
Other, net	(35)	(10)
Net cash provided by (used in) financing activities	(467)	(64)
Exchange rate effects on cash and cash equivalents	4	(29)
Net increase (decrease) in cash and cash equivalents	285	172
Cash and cash equivalents as of beginning of period	967	780
Cash and cash equivalents as of end of period	1,252	952
Parent Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	447	549
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	0	0
Other, net	0	0
Net cash provided by (used in) investing activities	0	0
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	0	0
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	0	0
Repayments of long-term debt	0	0
Purchases of treasury stock, including related fees	(300)	(420)
Dividends to parent	0	0
Contributions from parent	0	0
Stock option exercises	3	2
Series A common stock dividends	(150)	(131)
Return of capital to parent	0	0
(Distributions to) contributions from noncontrolling interests	0	0
Other, net	0	0
Net cash provided by (used in) financing activities	(447)	(549)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	0	0
Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	437	507
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	145	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	(283)	(342)
Other, net	0	0
Net cash provided by (used in) investing activities	(138)	(342)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(344)	374
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	1,589	15
Repayments of long-term debt	(1,082)	(7)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	(447)	(547)
Contributions from parent	0	0
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	0
(Distributions to) contributions from noncontrolling interests	0	0
Other, net	(13)	0
Net cash provided by (used in) financing activities	(297)	(165)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	2	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	2	0
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	299	406
Investing Activities
Capital expenditures on property, plant and equipment	(100)	(100)
Acquisitions, net of cash acquired	0	(3)
Proceeds from sale of businesses and assets, net	1	0
Capital expenditures related to Fairway Methanol LLC	0	(19)
Return of capital from subsidiary	750	0
Contributions to subsidiary	0	(92)
Intercompany loan receipts (disbursements)	(9)	(29)
Other, net	(9)	(12)
Net cash provided by (used in) investing activities	633	(255)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	6	2
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	746	345
Repayments of long-term debt	(635)	(3)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	(398)	(569)
Contributions from parent	0	0
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	0
(Distributions to) contributions from noncontrolling interests	0	0
Other, net	(20)	(9)
Net cash provided by (used in) financing activities	(301)	(234)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	631	(83)
Cash and cash equivalents as of beginning of period	21	110
Cash and cash equivalents as of end of period	652	27
Non-Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	602	380
Investing Activities
Capital expenditures on property, plant and equipment	(86)	(68)
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	7	0
Capital expenditures related to Fairway Methanol LLC	0	(244)
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	90	(15)
Other, net	(5)	(15)
Net cash provided by (used in) investing activities	6	(342)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	0	(1)
Proceeds from short-term borrowings	39	40
Repayments of short-term borrowings	(76)	(60)
Proceeds from long-term debt	0	0
Repayments of long-term debt	(11)	(11)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	0	0
Contributions from parent	0	92
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	(895)	0
(Distributions to) contributions from noncontrolling interests	(15)	187
Other, net	(2)	(1)
Net cash provided by (used in) financing activities	(960)	246
Exchange rate effects on cash and cash equivalents	4	(29)
Net increase (decrease) in cash and cash equivalents	(348)	255
Cash and cash equivalents as of beginning of period	946	670
Cash and cash equivalents as of end of period	598	925
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(845)	(1,116)
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	(895)	0
Contributions to subsidiary	0	92
Intercompany loan receipts (disbursements)	202	386
Other, net	0	0
Net cash provided by (used in) investing activities	(693)	478
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(9)	(29)
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	(826)	(360)
Repayments of long-term debt	633	3
Purchases of treasury stock, including related fees	0	0
Dividends to parent	845	1,116
Contributions from parent	0	(92)
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	895	0
(Distributions to) contributions from noncontrolling interests	0	0
Other, net	0	0
Net cash provided by (used in) financing activities	1,538	638
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	$ 0	$ 0